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1. What is PCI bus (Peripheral Component Interconnect Bus).

Short for  P eripheral C omponent  I nterconnect, a local bus standard developed by Intel

Corporation. Most modern PCs include a PCI bus in addition to a more general ISA expansion bus.

PCI is also used on newer versions of the Macintosh computer.

PCI is a 6!bit bus" though it is usually implemented as a #$!bit  bus. It can run at cloc% speeds of ##

or 66 M&'. At #$ bits and ## M&'" it yields a throughput rate of (## M)ps.

2. What is cache (Internal & External ) memory.

Cache memory is random access memory (RAM) that a computer microprocessor canaccess more quickly than it can access regular RAM. As the microprocessor processes data,it looks first in the cache memory and if it finds the data there (from a previous reading ofdata), it does not have to do the more time-consuming reading of data from larger memory.

Cache memory is sometimes descried in levels of closeness and accessiility to themicroprocessor. An *( cache is on the same chip as the microprocessor. (!or e"ample, the

PowerPC #$% processor has a &' kiloyte level-% cache uilt into its chip.) *$ is usually aseparate static RAM (S+AM) chip. he main RAM is usually a dynamic RAM (,+AM) chip.

n addition to cache memory, one can think of RAM itself as a cache of memory for hard dis%  storage since all of RAM*s contents come from the hard disk initially +hen you turn yourcomputer on and load the operating system (you are loading it into RAM) and later as youstart ne+ applications and access ne+ data. RAM can also contain a special area called adis% cache that contains the data most recently read in from the hard disk.

Pronounced cash" a special high!speed storage mechanism. It can be either a reserved section of main

memory or an independent high!speed storage device. -wo types of caching are commonly used in

 personal computers memory caching  and disk caching .

A memory cache" sometimes called a cache store or RAM cache" is a portion of memory made of

high!speed static +AM /S+AM0 instead of the slower and cheaper dynamic +AM /,+AM0 used for

main memory. Memory caching is effective because most programs access the same data or

instructions over and over. )y %eeping as much of this information as possible in S+AM" the

computer  avoids accessing the slower ,+AM.

Cache memory is random access memory (RAM) that a computer microprocessor can access morequickly than it can access regular RAM. As the microprocessor processes data, it looks first in thecache memory and if it finds the data there (from a previous reading of data), it does not have to dothe more time-consuming reading of data from larger memory.

Cache memory is sometimes descried in levels of closeness and accessiility to the microprocessor. An *( cache is on the same chip as the microprocessor. (!or e"ample, the PowerPC #$% processor

has a &' kiloyte level-% cache uilt into its chip.) *$ is usually a separate static RAM (S+AM) chip.he main RAM is usually a dynamic RAM (,+AM) chip.

n addition to cache memory, one can think of RAM itself as a cache of memory for hard dis%  storagesince all of RAM*s contents come from the hard disk initially +hen you turn your computer on and loadthe operating system (you are loading it into RAM) and later as you start ne+ applications and accessne+ data. RAM can also contain a special area called a dis% cache that contains the data most recentlyread in from the hard disk.

3. What type o mo!ems are there.

/m12dem0 (n.) Short for modulator-demodulator. A modem is a device or program that enables a

computer  to transmit data over" for example" telephone or cable lines. Computer information is stored digitally" whereas information transmitted over telephone lines is transmitted in the form of analog 

waves. A modem converts  between these two forms.

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3ortunately" there is one standard interface for connecting external modems to computers called RS-

232. Conse4uently" any external modem can be attached to any computer that has an +S!$#$ port"

which almost all  personal computers have. -here are also modems that come as an expansion board 

that you can insert into a vacant expansion slot. -hese are sometimes called onboard  or internal

modems.

". What is #$I% an! its types an! mirrorin.

/r5d0 Short for  Redundant  Array of  I ndependent (or  I nepensi!e"  Disks, a category of dis% drives thatemploy two or more drives in combination for  fault tolerance and performance. +AI, dis% drives are

used fre4uently on servers but arent generally necessary for personal computers.

-here are number of different +AI, levels

Level 0 -- Striped Disk Array without Fault Tolerance: Provides data striping  

/spreading out bloc%s of each file across multiple dis% drives0 but no redundancy. -his

improves performance but does not deliver fault tolerance. If one drive fails then all data in

the array is lost.

Level -- !irrorin" and Duple#in": Provides dis% mirroring. *evel ( provides twice

the read transaction rate of single dis%s and the same write transaction rate as single dis%s.

Level $ -- %rror-&orrectin" &odin": 7ot a typical implementation and rarely used"

*evel $ stripes data at the bit level rather than the bloc% level. Level ' -- it-nterleaved *arity: Provides byte!level striping with a dedicated parity

dis%. *evel #" which cannot service simultaneous multiple re4uests" also is rarely used.

Level + -- Dedicated *arity Drive: A commonly used implementation of +AI," *evel

 provides bloc%!level striping /li%e *evel 80 with a parity dis%. If a data dis% fails" the parity

data is used to create a replacement dis%. A disadvantage to *evel is that the parity dis% can

create write bottlenec%s.

Level , -- lock nterleaved Distriuted *arity: Provides data striping at the byte level

and also stripe error correction information. -his results in excellent performance and good

fault tolerance. *evel 9 is one of the most popular implementations of +AI,.

Level -- ndependent Data Disks with Doule *arity: Provides bloc%!level striping

with parity data distributed across all dis%s.

Level 0/ A !irror o1 Stripes: 7ot one of the original +AI, levels" two +AI, 8

stripes are created" and a +AI, ( mirror is created over them. :sed for both replicating and

sharing data among dis%s.

Level 0 A Stripe o1 !irrors: 7ot one of the original +AI, levels" multiple +AI, (

mirrors are created" and a +AI, 8 stripe is created over these.

Level 2: A trademar% of Storage Computer Corporation that adds caching to *evels # or

.

3AD S ;MC Corporations proprietary striped pairty +AI, system used in its

Symmetrix storage systems.

'irrorin

Mirroring involves having two copies of the same data on separate hard drives or drive

arrays. So basically the data is effectively mirrored on another drive. -he system basically

writes data simultaneously to both hard drives. -his is one of the two data redundancy

techni4ues used in +AI, to protect from data loss. -he benefit is that when one hard drive or

array fails" the system can still continue to operate since there are two copies of data.

,owntime is minimal and data recovery is relatively simple. All you need to do is rebuild the

data from the good copy.

-he following diagram illustrates how mirroring actually wor%s. <f course" this is a

simplified diagram. A" )" and C are separate files that reside on each dis%. ,is% ( and $ inthis diagram dont necessarily have to be dis%s themselves. -hey can be arrays of drives. -he

main thing to remember here is that the +AI, controller writes the same data bloc%s to each

mirrored drive. ;ach drive or array has the same information in it. =ou can even add another

level of complexity by introducing striping" which will be discussed shortly. Im not going to

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get into what striping is now if youre not familiar with it" but >ust %now it increases

 performance. If you have one striped array" you can mirror the array at the same time on a

second striped array. It can get very complicated. -o set up mirroring the number of drives

will have to be in the power of $ for obvious reasons.

-he drawbac% here is that both drives are tied up during the writing process which limits

 parallelism and can hurt performance. In contrast" mirroring has a performance increase when

dealing with reads. A good +AI, controller will only read from one of the drives since the

data on both are the same. ?hile the other is used to read" the free drive can be used for otherre4uests. -his increases parallelism" which is pretty much the concept behind the

 performance increase of +AI,.

Mirroring may seem li%e a good solution to ensure the safety of data. &owever" the trade off

here is the cost and wasted space involved with having two copies of the same data. =ou will

need twice as much storage space to mirror the data. It can be cost effective for some

applications where downtime can mean the downfall of a company or even loss of human

life. Most of the time" however" it might not be worth it. ,ata might not be that critical to

warrant spending twice as much on storage. -he alternative to mirroring is parity" which is

what the next section deals with.

. o* motherboar! communicate *ith +, (throuh I-+ port &

I#,)

 An R (nterrupt Reuest) is a physical connection on the motheroard through +hich a piece ofhard+are communicates +ith the C and the /01 the C responds through an 2/ (input2output)memory address. he so-called 0tandard R assignments date ack to the early days of 3/0 and4indo+s &.".

n the ad old days, Rs had to e assigned manually, either y means of physical s+itches, 5umpers, or +ith soft+are. 6ven no+, you may occasionally have to assign an R manually.

/. %i0erence bet*een $1/ at32 & 4,

FATFile Allocation Table. A disc filing system used by Windows to establish the

'layout' of your hard drive. There are two different types of FAT: FAT16 andFAT!" differentiated by the fact that FAT16 is 16#bit and FAT! is !#bit. $n

essence" FAT16 gives faster disc access" while FAT! delivers more space due tothe smaller minimum data cluster si%e.

5. ell somethin on CPIP - +,I 'o!el (I,+).

Summary -CP and IP were developed by a ,epartment of ,efense /,<,0 research pro>ectto connect a number different networ%s designed by different vendors into a networ% of

networ%s /the @Internet@0. It was initially successful because it delivered a few basic services

that everyone needs /file transfer" electronic mail" remote logon0 across a very large number

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of client and server systems. Several computers in a small department can use -CPIP /along

with other protocols0 on a single *A7. -he IP component provides routing from the

department to the enterprise networ%" then to regional networ%s" and finally to the global

Internet. <n the battlefield a communications networ% will sustain damage" so the ,<,

designed -CPIP to be robust and automatically recover from any node or phone line failure.

-his design allows the construction of very large networ%s with less central management.

&owever" because of the automatic recovery" networ% problems can go undiagnosed and

uncorrected for long periods of time.

As with all other communications protocol" -CPIP is composed of layers

• IP - is responsible for moving packet of data from node to node. IPforwards each packet based on a four byte destination address (the IPnumber. !he Internet authorities assign ranges of numbers to di"erentorgani#ations. !he organi#ations assign groups of their numbers todepartments. IP operates on gateway machines that move data fromdepartment to organi#ation to region and then around the world.

• CP - is responsible for verifying the correct delivery of data from client toserver. $ata can be lost in the intermediate network. !%P adds support to

detect errors or lost data and to trigger retransmission until the data iscorrectly and completely received.

• ,oc6ets 7 is a name given to the package of subroutines that provideaccess to !%P&IP on most systems.

 !here are three levels of !%P&IP knowledge

'. !he IP address assigned to this personal computer

. !he part of the IP address (the subnet mask that distinguishes othermachines on the same )A* (messages can be sent to them directly from

machines in other departments or elsewhere in the world (which are sentto a router machine

+. !he IP address of the router machine that connects this )A* to the rest ofthe world.

8. What is the !i0erence bet*een s*itch an! ub.

A hub is a fairly simple device that connects the computers. $f we use the e&ample of aphone system" it is lie a constant conferance call. (very one can tal and listen to everyone else" and if $ spea to )ac" )erry can here what $ say" even if he does not careabout what $ am taling about. (veryone must tae turns speaing.

With a switch however" things are more controled and it is more lie the way the phone

wors most of the time. $f you want to tal to someone" you dial their number" and ifthey are not screening their calls *to avoid you...+ they answer and you can tal.

The switch eeps trac of the ,A- addresses of all the computers that are connected toit and when one computer wants to tal to another" the switch transfers the databetween the two. $ thin the switch also allows other computers to also tal to eachother at the same time.

While most people may never now the difference" it is always better to have a switchthan a hub" and for some environsments where there is a /T of networ traffic it can

really help 0uite a bit *no pun intended+.

ateway: -onnects two different data protocols. A cable modem or 23 modem are gateways.$n the cable modem e&ample" the coa& cable is converted to a -AT4 ethernet cable" and a 23modem converts a telephone cable to -AT4

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5outers: 5outers connect two different subnets together" allowing the ability for different networsunder different domains to tal. A networ with a !44.!44.!44. subnet can tal to a!44.!44.!47 subnet via the router.

8ubs: 3plit the networ connection & amount of ways. For e&ample" a ! port hub will literallyswitch one connection ! ways. The problem9 acet collisions. There are revisions to fi& this asset forth in the $((( ;!. standard

3witches: 3mart hubs with memory" processors" and little operating systems. 3witches recogni%e

what device is broadcasting what. $f a computer maes a re0uest" say an internet page" theswitch will grab the page and send it to the proper computer" not all. Also" switches are ,A-address oriented while routers" hubs" and gateways are all $ address based.

9. What is %omain

A domain in A$ is nothing but logical grouping of ob,ects like userscomputers printers ./.

$cti:e %irectoryA networ% service that identifies all resources on a networ%  and ma%es them accessible to users and

applications. +esources include e!mail addresses" computers" and peripheral devices such as printers. Ideally" the directory service should ma%e the physical networ% topology and

 protocols transparent so that a user on a networ% can access any resource without %nowing

where or how it is physically connected.

-here are a number of directory services that are used widely. -wo of the most important

ones are *,AP" which is used primarily for e!mail addresses" and  #et$are %irectory Ser!ice

(#%S"" which is used on 7ovell 7etware networ%s. Birtually all directory services are based

on the .988 I-: standard" although the standard is so large and complex that no vendor

complies with it fully.

%irectory ,E#;ICE I4 4A directory service is an important part of a distributed computing environment thatprovides a way to locate and identify the users and resources available in the system. $n

its simplest form" directory services are lie the white pages of a telephone boo: <singspecific input *a person's name+" a user can receive specific output *a person's addressand telephone number+. 2irectory services also provide the functionality of the yellowpages#using general input *that is" where are the printers9+" a user can receive abrowsable listing of printer resources.

Windows =T 2irectory 3ervice in version 7. accommodates a larger number of ob>ects.reviously" the recommended ma&imum number of trusted domains was 1!;. $nWindows =T 3erver 7." the ocal 3ecurity Authority component has been enhanced toallow a greater number of trusted domains and to allow that number to scale with servermemory.

1<. What !o you 6no* about $%C

Active $irectory %oncepts

Active $irectory has several components that work together to provide acomplete directory service. !hey are as under 0

+b=ects an! $ttributes >  In A$1 every component is called as +b=ects andevery ob,ects as some $ttributes. 2g. users computer printers are called asob,ects and properties related to it is called as Attributes

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Class > A Class is nothing but a container or a ob,ect containing sub ob,ects like3orest !ree $omain ./. etc.

,chema > 1chema in nothing but a structure which de4ne what ob,ects and theirattributes can be stored in A$1. 5hen a domain is setup it contains a defaultschema know as $I! ($irectory Information !ree. !here are over '67 prede4nesclasses and over 867 attributes stored in $I!. ,C''?'.',C is used to view

the schema of A$1

%omains > A domain in A$ is nothing but logical grouping of ob,ects like userscomputers printers ./.

rees > !hey are logical grouping of $omains and 1ub-$omains under a singlehiraracery.

orest >  !hey are logical grouping of !rees having multiple namespace.

+ranisation @nit > It is a sub-division of domain into multiple logical classesby administration for easy administration and management of ob,ects in a

container.

%omain Controller 0 $% is an ob,ect or %omputer which runs 5indows 7771erve perating 1ystems and which maintains a copy of A$. In a domain we canhave multiple $%s according to our re9uirement.

?lobal Catalo > :% is called as inde; 4le which helps to 4nd ob,ects in a largeA$1. It is maintained by $%. 5hen a users logs on the a machine the :%searches for ob,ect match and send the ob,ect 9uery to the speci4c domain.

11. Explain %4, WI4, %CP.

T&*4*-ransmission Control ProtocolInternet Protocol /-CPIP0 is the most popular protocol" and

the basis for the Internet. Its routing capabilities provide maximum flexibility in an

enterprise!wide networ%. <n a -CPIP networ%" you must provide IP addresses to clients.

Clients may also re4uire a naming service or a method for name resolution li%e ,7S or

?I7S. ;very computer on a -CPIP networ% must have a uni4ue computer name and IP

address. -he IP address /together with its related subnet mas%0 identifies both the host

computer and the subnet to which it is attached. -CPIP address composed of #$ bit IP

address from range of 8.8.8.8. to $99.$99.$99.$99.

D5S-he ,omain 7ame System /,7S0 is an Internet and -CPIP standard name service. -he ,7S

service enables client computers on your networ% to register and resolve ,7S domain names

to IP address.

D6&*,ynamic &ost Configuration Protocol /,&CP0 is a -CPIP standard for simplifying

management of host IP configuration. -he ,&CP standard provides for the use of ,&CP

servers as a way to manage dynamic allocation of IP addresses and other related

configuration details to ,&CP!enabled clients on your networ%.?hen you move a computer to a different subnet" the IP address must be changed. ,&CP

allows you to dynamically assign an IP address to a client from a ,&CP server IP address

database on your local networ%

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75S?indows Internet 7ame Service /?I7S0 provides a dynamic replicated database service that

can register and resolve 7et)I<S names to IP addresses used on your networ%. ?indows

$888 Server provides ?I7S" which enables the server computer to act as a 7et)I<S name

server and register and resolve names for ?I7S!enabled client computers on your networ% as

described in the 7et)I<S over -CPIP standards.

12. o* !o you !o trust relationship bet*een 2 or !omains in4

rust #elationships

A trust relationship is a link between two domains in which the trustingdomain honors the logon authentication of the trusted domain. Active $irectorysupports two forms of trust relationships

ypes o rustD   Implicit t*o7*ay transiti:e trustD   Explicit one7*ay non7transiti:e trust

Implicit t*o7*ay transiti:e trust. A relationship between parent and child domains within a tree and between thetop-level domains in a forest. !his is the default< trust relationships amongdomains in a tree are established and maintained implicitly (automatically.

 !ransitive trust is a feature of the =erberos authentication protocol whichprovides the distributed authentication and authori#ation in 5indows 777.

 !ransitive trust between domains eliminates the management of interdomaintrust accounts. $omains that are members of the same tree automaticallyparticipate in a transitive bidirectional trust relationship with the parent domain.As a result users in one domain can access resources to which they have been

granted permission in all other domains in a tree.

ExampleA =erberos transitive trust simply means that if $omain A trusts $omain > and$omain > trusts $omain % then $omain A trusts $omain %. As a result adomain ,oining a tree immediately has trust relationships established with everydomain in the tree. !hese trust relationships make all ob,ects in the domains ofthe tree available to all other domains in the tree.

Example o rust #elationship

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Explicit one7*ay nontransiti:e trust.A relationship between domains that are not part of the same tree. Anontransitive trust is bounded by the two domains in the trust relationship and

does not ?ow to any other domains in the forest. In most cases you muste;plicitly (manually create nontransitive trusts. A one-way nontransitive trust isshown where $omain % trusts $omain ' so users in $omain ' can accessresources in $omain %. 2;plicit one-way nontransitive trusts are the only form oftrust possible with

D A 5indows 777 domain and a 5indows *! domainD A 5indows 777 domain in one forest and a 5indows 777 domain in

another forest.D A 5indows 777 domain and an MI! =erberos @ realm allowing a client

in a =erberos realm to authenticate to an Active $irectory domain in orderto access network resources in that domain

13. What is the use o host & lmhost Ale an! *hat !oes itcontain

HOST FILE

he short ans+er is that the 7osts file is like an address ook. 4hen you type anaddress like +++.yahoo.com into your ro+ser, the 7osts file is consulted to see ifyou have the address, or 8telephone numer,8 for that site. f you do, then yourcomputer +ill 8call it8 and the site +ill open. f not, your computer +ill ask your 0*s(internet service provider) computer for the phone numer efore it can 8call8 that

site. Most of the time, you do not have addresses in your 8address ook,8 ecauseyou have not put any there. herefore, most of the time your computer asks for the address from your 0 to find sites.

f you put ad server names into your 7osts file +ith your o+n computer*s address,your computer +ill never e ale to contact the ad server. t +ill try to, ut it +ill esimply calling itself and get a 8usy signal8 of sorts. 9our computer +ill then give upcalling the ad server and no ads +ill e loaded, nor +ill any tracking take place. 9ourchoices for locking sites are not 5ust limited to locking ad servers. 9ou may locksites that serve advertisements, sites that serve o5ectionale content, or any othersite that you choose to lock.

Try to locate any existing hosts file on your computer:

Windows 95/98/Me c:\windows\hosts

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Windows NT/2000/XP Pro  c:\winnt\system!\dri"ers\etc\hosts 

Windows XP Home c:\windows\system!\dri"ers\etc\hosts 

#enefits of the Hosts File:

$%&' (ses less resources:

:y using a function uilt into your computer, you +ill e ale to lock advertisingsites (or any other site you +ish) +ithout the need for any e"tra programs. his +illcut do+n on memory and processor usage, +hich +ill free up your resources forother tasks.

$!&' )or*s on connections other than HTT+:

Most ad-locking programs +ill only intercept calls going to the 7 (or +e)port on your computer. /ther transfers can still get through. he 7osts file, ho+ever,+ill lock calls on any port, +hether it is 7, !, or +hatever else you happento e doing.

$&' Eliminate many trac*ing and pri"acy concerns:

:y intercepting the calls efore they ever leave your computer, the 7osts file canprevent advertising and tracking companies from ever even kno+ing you are vie+inga +e page. his +ill keep them from profiling you and help you keep your privacy. All sites in the 7osts file entered +ith a %';.$.$.% address +ill never e accessed.0ites that are not in the 7osts file may still track you and send you ads. 0ee thenotes section for more information.

o find out +hich advertisers may e tracking you, please visit this e"cellent +esite.

$,&' The Hosts file is configura-le:

Rather than relying on others to decide +hat sites to lock for you, you may edit the7osts file entirely on your o+n. his means you can put any site you +ish into the7osts file and that site +ill not e ale to e accessed. 9ou can use this to lockadvertisers, trackers, or sites you +ould not +ant your small children to see. 9ou getto decide entirely +hat you +ish to lock, and you don*t have to depend on someoneelse*s 5udgement<

$.&' Increased -rowsing speed:

:y placing sites into your 7osts file +ith their correct addresses, your computer doesnot need to ask another computer +here to find a site. his can significantly speedup your surfing e"perience ecause your computer +ill go straight to that site insteadof having to ask directions. Also, y keeping ads from eing loaded using thelocking technique in the 7osts file, +e pages +ill e vie+ale much more quicklysince they +on*t have to load a lot of fancy graphics.

Some restrictions on the Hosts file:

$%&' It will not wor* with wildcards/ such as 0&whate"eryouwantgoeshere&com&

$!&' It will not wor* with (1L2s that -egin with I+ num-ers&

numers are the numerical equivalent of the +++.somesitenamehere.comaddress, and that is +hat your computer actually uses to find the +e page. henames are there so that humans don*t have to rememer long strings of numers.

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9ou +ould need to find the +++.+hatever.com address that the numerrepresents, and then lock that name instead of using the numer. !or e"ample,9ahoo<*s address is +++.yahoo.com, and its address is '$=.;%.'$$.#; 4e canlock +++.yahoo.com ut not the address. he reason for this is that 7osts isused to determine addresses. f +e already kno+ the address, 7osts +ill not econsulted and so can not lock the site. do not recommend actually locking9ahoo< though, as it is a great search engine<

$&' It will not wor* with ads that are ser"ed from the same site you are"iewing&

he reason for this is that the 7osts file must lock an entire site, and can not locksudirectories or pathnames on a site. !or e"ample, you could not lock+++.netscape.com2ads2 ecause you can*t lock sudirectories. 9ou +ould need tolock the entire +++.netscape.com server, and that +ould leave you +ithout accessto >etscape*s site. 0o you +ill have to use a different method to eliminate ads thatcome from the site you are vie+ing, such as an ad-locking program.

$,&' It may cause some sites to 3uit wor*ing properly&

f you put the +rong server into your hosts file, it may mean that certain +esites +illno longer e vie+ale as they normally +ould e. o remedy this, remove the entryof the site you +ish to unlock from your hosts file. lease see the !A section formore on this. n particular, you may notice sites that rely on Akamai*s servers +ill notfunction properly if Akamai is in your 7osts file.

The L!68STS File-he *M&<S-S file is a static ASCII file used to resolve 7et)I<S names to IP addresses of

remote computers running ?indows 7- and other 7et)I<S!based hosts. -his method is

oldest method of resolving computer name to IP address. ;very client must have this file inorder to resolve 7et)I<S names. It is located in winnt9syste'$9drivers9etc directory.

&ontents o1 L!68ST File

;*3% : ,efines which entries should be initially preloaded as permanent entries in the name

cache. Preloaded entries reduce networ% broadcasts" because names are resolved from cache

rather than from broadcast or by parsing the *M&<S-S file. ;ntries with a EP+; tag are

loaded automatically at initiali'ation or manually by typing ntstat -3  at a command prompt.

;D8!:<doain=nae> : 3acilitates domain activity" such as logon validation over a router"

account synchroni'ation" and browsing.

;58F53 : Avoids using 7et)I<S!directed name 4ueries for older *A7 Manager :7Isystems.

;%?5=ALT%35AT% @ ;%5D=ALT%35AT% : ,efines a redundant list of alternate

locations for *M&<S-S files. -he recommended way to EI7C*:,; remote files is using a

:niversal 7aming Convention /:7C0 path" to ensure access to the file. <f course" the :7C

names must exist in the *M&<S-S file with a proper IP address to 7et)I<S name

translation.

;5&LD% : *oads and searches 7et)I<S entries in a separate file from the default

*M&<S-S file. -ypically" an EI7C*:,; file is a centrally located shared *M&<S- file.

;!6 : Adds multiple entries for a multihomed computer.

1". *hat are the beneAts o Ale an! print ser:er

print ser:er

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he beneAt of having a print server is you can have many Macintoshes print toone )aser5riter. >y using the direct method you get into a waiting game. !he4rst one who looks for it when it is idle gets it. !he Print 1erver 9ueues up allprinting re9uests and makes sure the printer has no idle time as long as a print

 ,ob is ready. !he Bueue above shows there is one print ,ob printing and theserver is waiting for another print ,ob. !he )og above shows you any messageswhich came from the Printer

1. What is I,%4 - ease line

I,%4

(ntegrated 0ervices 3igital >et+ork) - 3igital telephony scheme that allo+s a user to connect to thenternet over standard phone lines at speeds higher than a ?#@ modem allo+s.

Abbreviation of i ntegrated ser!ices d igital net$ork " an international communications standard for

sending voice" video" and data over  digital telephone lines or normal telephone wires. IS,7 supports 

data transfer rates of 6 Fbps /6"888  bits per second0.

-here are two types of IS,7

• )asic +ate Interface /)+I0 !! consists of two 6!Fbps )!channels and one ,!channel for

transmitting control information.

• Primary +ate Interface /P+I0 !! consists of $# )!channels and one ,!channel /:.S.0 or #8 )!

channels and one ,!channel /;urope0.

-he original version of IS,7 employs baseband transmission. Another version" called )!IS,7" uses

 broadband transmission and is able to support transmission rates of (.9 Mbps. )!IS,7 re4uires fiber

optic cables and is not widely available.

ease line

4 dedicated 5ommon carrier circuit pro"iding point6to6point or multipoint networ* connection/reser"ed for the permanent and pri"ate use of a customer & 4lso called a +ri"ate Line& 4dedicated 5ommon carrier circuit pro"iding point6to6point or multipoint networ* connection/reser"ed for the permanent and pri"ate use of a customer & 4lso called a +ri"ate Line&

A *eased *ine" also %nown as a Gprivate circuitH or G-( leased lineH" is a permanent dedicated

communication lin% between two points. -he lin% is separate from the public telephone networ% and

is reserved exclusively for the leased line purchaser. ?here a companys Internet usage is intensive" a

leased line provides a far more cost!effective connectivity solution than more traditional ones such as

IS,7.

A leased line can be a twisted pair" coax or fibre optic cable and may involve all sorts of other

hardware such as coils" transformers" amplifiers and regenerators. *eased lines have varying datatransfer rates the highest being a -( line" which provides a maximum speed of (.9Mbps. -hese

transfer rates can be divided between voice and data signals using multiplexing techni4ues. If the

leased line is being used to carry voice data then the line can also be connected to a phone system.

*arge companies generally use leased lines to connect several geographically different networ%s

within their organisation. -he lease line is also widely used to connect offices to the web via a point of 

 presence /P<P0" which is a fast connection directly to the Internet. A -( leased line can connect over

hundreds of users to the Internet effortlessly as long they are >ust browsing" a problem would only

occur if they were to all start downloading files li%e MP#s.

1/. *hat is Clusterin

Clustering is a nonlinear activity that generates ideas" images and feelings around astimulus word. As students cluster" their thoughts tumble out" enlarging their word

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 ban% for writing and often enabling them to see patterns in their ideas. Clusteringmay be a class or an individual activity.

%lustering is the use of multiple computers and storage devices to createwhat seems to be a single system. %lustering is often used to increase asystemCs availability and for load balancing on highly-traDcked 5eb sites.A server architecture that emulates multiprocessing by interconnectingtwo or more individual computers in order to share the applicationprocessing load. MicrosoftCs future clustering technology for 5indows *!now carries the code name 5olfpack. A number of third parties o"erproprietary clustering hardware and software for 5indows *! 1erver 6.7.A techni9ue in which two or more servers are interconnected and canaccess a common storage pool. %lustering prevents the failure of a single

4le server from denying access to data and adds computing power to thenetwork for large numbers of users.

15. What is P%C & B%C

 A 3C is a rimary 3omain Controller, and a :3C is a :ackup 3omain Controller. 9ou mustinstall a 3C efore any other domain servers. he rimary 3omain Controller maintains themaster copy of the directory dataase and validates users. A :ackup 3omain Controllercontains a copy of the directory dataase and can validate users. f the 3C fails then a:3C can e promoted to a 3C. ossile data loss is user changes that have not yet eenreplicated from the 3C to the :3C. A 3C can e demoted to a :3C if one of the :3C*s ispromoted to the 3C.

18. *hat is P+P3 an! I'$P

+O+

/& (ost /ffice rotocol &) is the most recent version of a standard protocol for receiving e-mail.

/& is a client-ser:er protocol in +hich e-mail is received and held for you y your nternet

server. eriodically, you (or your client e-mail receiver) check your mail-o" on the server anddo+nload any mail, proaly using /&. his standard protocol is uilt into most popular e-mailproducts, such as 6udora and /utlook 6"press. t*s also uilt into the >etscape and Microsoft nternet

6"plorer ro+sers./& is designed to delete mail on the server as soon as the user has do+nloaded it. 7o+ever, someimplementations allo+ users or an administrator to specify that mail e saved for some period of time./ can e thought of as a 8store-and-for+ard8 service.

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 An alternative protocol is nternet Message Access rotocol (!A*). MA provides the user more

capailities for retaining e-mail on the server and for organiing it in folders on the server. MA cane thought of as a remote file server.

/ and MA deal +ith the receiving of e-mail and are not to e confused +ith the 0imple Mail

ransfer rotocol (S!T*), a protocol for transferring e-mail across the nternet. 9ou send e-mail +ith

0M and a mail handler receives it on your recipient*s ehalf. hen the mail is read using / orMA.

he conventional port nuer for /& is %%$.

 A port numer is a +ay to identify a specific process to +hich an nternet or other net+ork message isto e for+arded +hen it arrives at a server. !or the  !ransmission %ontrol Protocol and the /ser$atagram Protocol, a port numer is a %#-bit integer that is put in the header appended to amessage unit. his port numer is passed logically et+een client and server transport layers andphysically et+een the transport layer and the Internet Protocol layer and for+arded on.

!or e"ample, a request from a client (perhaps on ehalf of you at your C) to a server on the nternetmay request a file e served from that host*s !ile ransfer rotocol ( 3-P) server or process. n orderto pass your request to the ! process in the remote server, the ransmission Control rotocol(-CP) soft+are layer in your computer identifies the port numer of '% (+hich y convention isassociated +ith an ! request) in the %#-it port numer integer that is appended to your request. Atthe server, the C layer +ill read the port numer of '% and for+ard your request to the ! program

at the server.

0ome services or processes have conventionally assigned permanent port numers. hese arekno+n as well!%nown port numbers. n other cases, a port numer is assigned temporarily (for theduration of the request and its completion) from a range of assigned port numers. his is called anephemeral port numer.

I74+

MA (nternet Message Access rotocol) is a standard protocol for accessing e-mail from yourlocal server. MA (the latest version is MA Bersion =) is a client&server protocol in +hich e-mail isreceived and held for you y your nternet server. 9ou (or your e-mail client) can vie+ 5ust the headingand the sender of the letter and then decide +hether to do+nload the mail. 9ou can also create and

manipulate multiple folders or mailo"es on the server, delete messages, or search for certain parts or an entire note. MA requires continual access to the server during the time that you are +orking +ithyour mail.

 A less sophisticated protocol is ost /ffice rotocol & (P<P#). 4ith /&, your mail is saved for youin a single mailo" on the server. 4hen you read your mail, all of it is immediately do+nloaded to your computer and, e"cept +hen previously arranged, no longer maintained on the server.

MA can e thought of as a remote file server. /& can e thought of as a 8store-and-for+ard8service.

P<P# and IMAP deal with the receiving of e!mail from your local server and are not to be

confused with Simple Mail -ransfer Protocol /SM-P0" a protocol used for exchanging e!mail

 between points on the Internet. -ypically" SM-P is used for sending only and P<P# or IMAP

are used to read e!mail.

6ow will you ove ailo# 1ro one site to other

 !he /sers have outlook 777 point to the $omainA.%M Mailbo;. 2;change is set toforward and not leave a copy any messages sent to the $omian>.*et mailbo; to the$omainA.%M Mailbo;.

It is done this way due to our %orporate 1tructure.$omainA is the %orporate 2ntity and $omain > is our $ivision.5e Primarily %ommunicate as $omainA but occasionally we need to send messages out

as $omain >. !Ee users know to enter their $omain > account in 1ent 3rom so it goesout correctly.

 !his Method works great e;cept for one thing.5e have :3I Main 2ssentials as our 1PAM 4lter.

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It is automatically set up to put any 1PAM messages in a 1PAM folder in the Mailbo; itwas sent to. !he 1PAM messages for the $omain > mailbo; are not being forwarded tothe $omain A mailbo;.

My only solution so far (!EA! MAF 5R= is to set thier utlook to also open mailbo; >and put the 1PAM folder in the utlook >ar. Eowever not all users use the utlook >arand I do not want them having to look at multiple folders for 1PAMI tried to put a Rule in the 1PAM folder to move it but Rules only applied to the Inbo;. Ialso tried on the 2;chage server to go to the M $rive *avigated to the 1PAM folder and

move the messages to the %orrect 1PAM folder. I get an error that the messages alreadye;hists when I do that. If I %opy than $elete I can move them in the M $rive but whenchecking utlook they are still in the rigianal 1PAM foler..

19. o* *ill you restore the bac6up in exchane (oine - +nline)

6mail systems depend on many hard+are and soft+are components. f any elementfails to operate in the required manner, if the hard+are suffers a catastrophic failure,or if a physical disaster such as an electricity outage afflicts the hard+are, you musthave good system ackups to get users ack online as quickly as possile.

he 6"change '$$$ 0erver installation procedure enhances the standard 4indo+s'$$$ 0erver :ackup utility (ntackup.e"e) to support the 6"change 0tore*stransactional nature. hese enhancements add support for 6"change '$$$*s .edand .stm file formats, let ackup agents (i.e., ntackup.e"e or third-party products)copy dataases to tape +ithout shutting do+n 6"change services, and let you select+hich servers and dataases to ack up or restore. nderstanding the asics of themost important and useful disaster-recovery processesincluding full ackups,snapshot and clone ackups, and the general recovery procedurecan help youprepare for disasters and recover from them quickly.

2<. What is ;P4

pronounced as separate letters 1hort for v irtual private network, a network  thatis constructed by using public wires to connect nodes. 3or e;ample there are anumber of systems that enable you to create networks using the Internet as themedium for transporting data. !hese systems use encryption and other security mechanisms to ensure that only authori#ed users can access the network andthat the data cannot be intercepted.

 A virtual private net+ork (B>) is a +ay to use a pulic telecommunication infrastructure, such asthe nternet, to provide remote offices or individual users +ith secure access to their

organiation*s net+ork. A virtual private net+ork can e contrasted +ith an e"pensive system ofo+ned or leased lines that can only e used y one organiation. he goal of a B> is to providethe organiation +ith the same capailities, ut at a much lo+er cost.

 A B> +orks y using the shared pulic infrastructure +hile maintaining privacy through securityprocedures and tunneling protocol s such as the Dayer +o unneling rotocol ( D' ). n effect,the protocols, y encrypting data at the sending end and decrypting it at the receiving end, sendthe data through a 8tunnel8 that cannot e 8entered8 y data that is not properly encrypted. Anadditional level of security involves encrypting not only the data, ut also the originating andreceiving net+ork addresses.

21. %i0erence P2 P3 P" Celeron

+entium ,

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he term you selected is eing presented y searchMoileComputing.com, aecharget site for Moile Computing professionals.

entium = (=) is the ntel processor (codenamed Willamette) that +as released in>ovemer '$$$. he = processor has a viale clock speed that no+ e"ceeds 'gigahert (:E#) - as compared to the % E7 of the Pentium +.

= had the first totally ne+ chip architecture since the %FF? entium ro. he ma5ordifference involved structural changes that affected the +ay processing takes place+ithin the chip, something ntel calls NetBurst microarchitecture. Aspects of thechanges includeG a '$-stage pipeline, +hich oosts performance y increasingprocessor frequency1 a rapid-e"ecution engine, +hich doules the core frequencyand reduces latency y enaling each instruction to e e"ecuted in a half (rather thana +hole) clock cycle1 a =$$ M7 system bus, +hich enales transfer rates of &.'gigaytes per second (E:ps)1 an execution trace cache, +hich optimies cachememory efficiency and reduces latency y storing decoded sequences of micro-operations1 and improved floating point and multimedia unit and adanced d!namicexecution, all of +hich enale faster processing for especially demanding

applications, such as digital video, voice recognition, and online gaming.

=*s main competition for processor market share is the AM, Athlon processor.

22. What is !ap.

. %$P (iht*iht %irectory $cess Protocol))$AP is protocol that de4ne how A$ service is designed and how ob,ectsare managed in A$s. It de4nes the schema of A$. It de4nes how ob,ectsare organi#ed in A$. It also de4nes how ob,ects or resources can be

access from A$. All ob,ects naming in A$ is based on )$AP protocol.

)$AP *amaing of ob,ects%*G1chema%*G%on4guration$%Gforest name$%Gforest root  

e 0 %*GA,ay Raul %*G/sers $*G@ision $%Gcom

In the above e;ample $=ay #aul is username 3ull name and ;ision.comis domain name

LDAP Ports-he connections via the *,AP protocol between a client and ,SA use either a -ransmission

Control Protocol /-CP0 or :ser ,atagram Protocol /:,P0. -he table below lists the protocol

soc%ets used in different access modes

unction Port)$AP +8H)$AP 1ecure 1ockets )ayer (11) +:lobal %atalog (:% +8:lobal %atalog 1ecure 1ockets )ayer +H

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2") What is $%,.

$cti:e %irectory ,upport iles

 !he engine used by Active $irectory is based on MicrosoftCs Jet database

technology. Jet uses a b-tree 4le structure with transaction logs to ensurerecoverability in the event of a system or drive failure.

5hen you promote a server to a domain controller you select where to put theActive $irectory 4les. !he default path is in the boot partition under\Windows\NTDS. :enerally it is a good idea to put them on a separate volumefrom the operating system 4les to improve performance.

2)What is !irectory ser:ice D an! *hat is acti:e !irectoryser:ice D

In simple a directory service can be de4ne as he rien!ly telephoneoperator *ho ui!es or loo6s up peopleFs phone numbers or yourassistance..  If the directory is the actual dataKthe list of people andtelephone numbersKthe operators and the method for calling them is thedirectory service. In windows 777 Active $irectory is a database whilethe computers which maintains this database are called as %omainControllers.

In the 4eld of computing there are various types of directory developedthe development of networking begins likeMicrosoft - Active $irectory 1ervice

Lero; - :rapevineI!/ - L.77I222 - $*1 ($omain *aming 1ervice*etware - *$1 (*ovell $irectory 1erviceR3% - )$AP ()ight 5eight $irectory Access Protocol

$cti:e %irectory ,er:ice

A$1 is a truly network directory that includes all the features and bene4tsof traditional directory service. In *ovember 'HH Microsoft delivered the

4rst preview of Active $irectory for developers at the Professional$evelopers %onference held in )ong >each %alifornia. Active $irectory isdesigned to be a single directory for any si#e of network. !heinformational (data) model of the )$AP protocol is a base for A$. Active$irectory is based on L.77 K the International 1tandards rgani#ation(I1 special standard de4ning elements of a distributed directory service. !his standard proposes an ob,ect-oriented data model< therefore it usessuch terms as class, objects and attributes

2/)o* bi is acti:e !irectory ser:ice D

$cti:e %irectory 0 '77777 users '77777 computers '7777 groups'7777 printers and '7777 volumes. !he si#e of the resulting *tds.dit isabout '677 M> or '.6 gigabytes !his is with minimal attributes set on

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the ob,ects. If all the attributes are set and new schema is update then thesi#e can grow too long.

25) What is ,chema D

1chema in nothing but a structure which de4ne what ob,ects and theirattributes can be stored in A$1. 5hen a domain is setup it contains adefault schema know as $I! ($irectory Information !ree. !here are over'67 prede4nes classes and over 867 attributes stored in $I!.,C''?'.',C is used to view the schema of A$1

28) What is encryptionD $n! ho* encryption *or6s D

Encryption >

2ncryption is a process of disguising a message or data in such a way as to hideits substance. Encryption is the process of converting data into a format thatcannot be read by another user. nce a user has encrypted a 4le the 4le

automatically remains encrypted whenever the 4le is stored on disk and no otheruser can decrypt it.

Decryption is the process of converting data from encrypted format back to itsoriginal format. nce a user has decrypted a 4le the 4le remains decryptedwhenever the 4le is stored on disk.

5indows 777 includes 2ncrypting 3ile 1ystem (231 allows users to store theiron-disk data in encrypted format. 2ncryption facility is available on for *!31partition only.

231 provides the following features0

• /sers can encrypt their 4les when storing them on disk. 2ncryption is as

easy as selecting a check bo; in the 4leCs Properties dialog bo;.

• Accessing encrypted 4les is fast and easy. /sers see their data in plainte;t when accessing the data from disk.

• 2ncryption of data is accomplished automatically and is completely

transparent to the user.

• /sers can actively decrypt a 4le by clearing the 2ncryption check bo; onthe 4leCs Properties dialog bo;.

• Administrators can recover data that was encrypted by another user. !his

ensures that data is accessible if the user that encrypted the data is nolonger available or has lost their private key.

231 only encrypts data when it is stored on disk. !o encrypt data as it istransported over a !%P&IP network two optional features are available--InternetProtocol security (IP1ec and PP!P encryption

o* Encryption *or6s

Encryption of 4les works as follows0

• 2ach 4le has a uni9ue le encryption key  which is later used to decrypt

the 4leCs data.

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•  !he 4le encryption key is in itself encrypted--it is protected by the userCs

public key corresponding to the userCs 231 certi4cate.

•  !he 4le encryption key is also protected by the public key of an authori#ed

recovery agent.

Decryption of 4les works as follows0

•  !o decrypt a 4le the 4le encryption key must 4rst be decrypted. !he 4le

encryption key is decrypted when the user has a private key that matchesthe public key.

•  !he user is not the only person that can decrypt the 4le encryption key. A

recovery agent can also decrypt the 4le encryption key by using therecovery agentCs private key.

• nce the 4le encryption key is decrypted it can be used by either the useror the recovery agent to decrypt the data in the 4le.

4+E > 2ncrypted data is not encrypted when in transit over the network butonly when stored on disk. !he e;ception to this is when your system includesInternet Protocol security (IP1ec. IP1ec encrypts data while it is transported overa !%P&IP network. 2ncrypted 4les are not accessible from Macintosh clients. Foucannot encrypt a compress 4le.

29) *hat is %, an! reasons or usin !sD (!istribute! Alesystem )

%istribute! Ale system o:er:ie*

 !he %istribute! Ale system (%s) allows system administrators to make iteasier for users to access and manage 4les that are physically distributed acrossa network. 5ith $fs you can make 4les distributed across multiple serversappear to users as if they reside in one place on the network. /sers no longerneed to know and specify the actual physical location of 4les in order to accessthem.

3or e;ample if you have marketing material scattered across multiple servers ina domain you can use $fs to make it appear as though all of the material resideson a single server. !his eliminates the need for users to go to multiple locationson the network to 4nd the information they need.

#easons or usin %s Fou should consider implementing $fs if0

• /sers who access shared folders are distributed across a site or sites.

• Most users re9uire access to multiple shared folders.

• 1erver load balancing could be improved by redistributing shared folders.

• /sers re9uire uninterrupted access to shared folders.

•  Four organi#ation has 5eb sites for either internal or e;ternal use.

ypes o %s

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/sing the $fs console you can implement a distributed 4le system in either oftwo ways--either as a stan!7alone !istribute! Ale system or as a !omain7base! !istribute! Ale system.

$ stan!7alone %s root>

• $oes not use Active $irectory.

• %annot have root-level $fs shared folders.

• Eas a limited hierarchy. A standard $fs root can have only a single level of

$fs links.

• Replication facility is not available.

$ !omain7base! %s root>

• Must be hosted on a domain member server.

• Eas its $fs topology automatically published to Active $irectory.

• %an have root-level $fs shared folders.

• $oes not have a limited hierarchy. A domain-based $fs root can have

multiple levels of $fs links.

• Replication facility is available.

3<)o* %CP *or6sD $n! *hat is %CP relay aentD

,&CP stands for @,ynamic &ost Configuration Protocol@.,&CP automatically assigns IP addresses to computers. ,&CP overcomes the limitations of

configuring -CPIP manually. ,&CP is an extension of the )oot Protocol /)<<-P0. )<<-P

enables dis%less clients to start up and automatically configure -CPIP. ,&CP centrali'es and

manages the allocation of -CPIP configuration information by automatically assigning IP

addresses to computers configured to use ,&CP. Implementing ,&CP eliminates some of the

configuration problems associated with manually configuring -CPIP.

;ach time a ,&CP client starts" it re4uests IP addressing information from a ,&CP server"

including the IP address" the subnet mas%" and optional values. -he optional values may

include a default gateway address" ,omain 7ame System /,7S0 address" and ?indows

Internet 7ame Service /?I7S0 server address. ?hen a ,&CP server receives a re4uest" it

selects IP addressing information from a pool of addresses defined in its database and offers it

to the ,&CP client. If the client accepts the offer" the IP addressing information is leased to

the client for a specified period of time. If there is no available IP addressing information in

the pool to lease to a client" the client cannot initiali'e -CPIP.

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6ow D6&* 7orks,&CP uses a four!phase process to configure a ,&CP client as given below

) * lease discover : -he client initiali'es a limited version of -CPIP and broadcasts a

re4uest for the location of a ,&CP server and IP addressing information.

$) * lease o11er : All ,&CP servers that have valid IP addressing information available sendan offer to the client.

') * lease reBuest : -he client selects the IP addressing information from the first offer it

receives and broadcasts a message re4uesting to lease the IP addressing information in the

offer.

+) * lease acknowled"ent : -he ,&CP server that made the offer responds to the

message" and all other ,&CP servers withdraw their offers. -he IP addressing information is

assigned to the client and an ac%nowledgment is sent. -he client finishes initiali'ing and

 binding the -CPIP protocol. <nce the automatic configuration process is complete" the client

can use all -CPIP services and utilities for normal networ% communications and connectivityto other IP hosts.

D6&* 3elay A"ent

A relay agent is a small program that relays ,&CP)<<-P messages between clients and

servers on different subnets. -he ,&CP +elay Agent component provided with the ?indows

$888 router is a )<<-P relay agent that relays ,&CP messages between ,&CP clients and

,&CP servers on different IP networ%s. 3or each IP networ% segment that contains ,&CP

clients" either a ,&CP server or a computer acting as a ,&CP relay agent is re4uired.

To add the D6&* 3elay A"ent 

• Clic% Start" point to Programs" point to Administrative -ools" then clic% +outing And

+emote Access.

• In the console tree" clic% Server nameIP +outingJeneral.

• +ight!clic% Jeneral" then clic% 7ew +outing Protocol.

• In the Select +outing Protocol dialog box" clic% ,&CP +elay Agent" then clic% <F.

31) +n !is6 manaement explain basic !is6 :s %ynamin !is6D

Basic !is6s are the logical disk structure that use the same disk structureused in 5indows *! 6.7 and previous operating systems all the way back

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to M1-$1. !hat is they are divided into primary and e;tended partitionsand logical drives can be created within e;tended partitions.

%ynamic !is6s use a new disk structure that was introduced in 5indows777 and now in windows 77+ .In dynamic disk partitions are called as;olumes. 5ith dynamic disks you can e;tend simple volumes (makethem bigger without reformatting and losing data to any empty space onany dynamic disk create spanned volumes across multiple physical disksand create fault tolerant (RAI$ ' and volumes.

/nlike basic disk dynamic disk does not use M>R to store partition table.Instead they use a private database at the end of the disk called as ;'(oical ;olume 'anaer). !his database is of 'M> and replicated to alldynamic in a machine. 5indows 77+ does not support 5indows *!partition that uses RAI$ level when you upgrade from *! to 77+.

 !he following are some limitations of using dynamic disks0

• $ynamic disks are currently not supported on laptop computers.

• Removable media and disks attached via 3ire5ire (I222 '+H6/niversal 1erial >us (/1> or shared 1%1I buses cannot beconverted to dynamic.

•  Fou can install 5indows 1erver 77+ only onto a dynamic volumethat was converted from a basic boot or system partition.Fou cannotinstall onto a dynamic volume that was created from free space.!hisis because there must be an entry in the partition table for the setupprogram to recogni#e the volume and such an entry does not e;iston a newly created dynamic volume.

• 2ven though 5indows 777 LP Professional and 1erver 77+ all

use dynamic disks you cannot convert a basic disk that holdsmultiple instances of these operating systems to dynamic.!heoperating systems installed on the disk will not start if you do this.

• $ynamic disks are not supported by 5indows %luster 1ervice. If youneed the features of dynamic disks on a clustered shared disk youcan use a third-party program called @eritas @olume Manager 6.7 toaccomplish this.

31) What is IC, ( intrnet connection sharin.)

nternet connection sharin"

?ith the Internet connection sharing feature of 7etwor% and ,ial!up Connections" you can

use ?indows $888 to connect your home networ% or small office networ% to the Internet. 3or 

example" you might have a home networ% that connects to the Internet by using a dial!up

connection. )y enabling Internet connection sharing on the computer that uses the dial!up

connection" you are providing networ% address translation" addressing" and name resolution

services for all computers on your home networ%.

After Internet connection sharing is enabled" and users verify their networ%ing and Internet

options" home networ% or small office networ% users can use applications such as Internet

;xplorer and <utloo% ;xpress as if they were already connected to the Internet Service

Provider /ISP0. -he Internet connection sharing computer then dials the ISP and creates the

connection so that the user can reach the specified ?eb address or resource. -o use the

Internet connection sharing feature" users on your home office or small office networ% must

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configure -CPIP on their local area connection to obtain an IP address automatically. Also"

home office or small office networ% users must configure Internet options for Internet

connection sharing.

-he Internet connection sharing feature is intended for use in a small office or home office

where networ% configuration and the Internet connection are managed by the computer

running ?indows $888 where the shared connection resides. It is assumed that on its

networ%" this computer is the only Internet connection" the only gateway to the Internet" and

that it sets up all internal networ% addresses.

=ou might need to configure applications and services on the Internet connection sharing

computer to wor% properly across the Internet. 3or example" if users on your home networ%

want to play the ,iablo game with other users on the Internet" you must configure the ,iablo

application on the connection where Internet connection sharing is enabled. Conversely"

services that you provide must be configured so that Internet users can access them. 3or

example" if you are hosting a ?eb server on your home networ% and want Internet users to be

able to connect to it" you must configure the ?eb server service on the Internet connection

sharing computer.

portant *oints• -o configure Internet connection sharing" you must be a member of the

Administrators group.• =ou should not use this feature in an existing networ% with other ?indows $888

Server domain controllers" ,7S servers" gateways" ,&CP servers" or systems

configured for static IPaddresses. If you are running ?indows $888 Server" and one

or more of these components exist" you must use networ% address translation to

achieve the same result.

• A computer with Internet connection sharing needs two connections. <ne connection"

typically a *A7 adapter" connects to the computers on the home networ%. -he other

connection connects the home networ% to the Internet. =ou need to ensure that

Internet connection sharing is enabled on the connection that connects your home

networ% to the Internet. )y doing this" the home networ% connection appropriatelyallocates -CPIP addresses to its own users" the shared connection can connect your

home networ% to the Internet" and users outside your home networ% are not at ris% of

receiving inappropriate addresses from your home networ%. )y enabling Internet

connection sharing on a connection" the Internet connection sharing computer

 becomes a ,ynamic &ost Configuration Protocol /,&CP0 allocator for the home

networ%. ,&CP distributes -CPIP addresses to users as they start up. If Internet

connection sharing is enabled on the wrong networ% adapter" users outside your home

networ% might be granted -CPIP addresses by the home networ% ,&CP allocator"

causing problems on their own networ%s.

?hen you enable Internet connection sharing" the adapter connected to the home or small

office networ% is given a new static IP address configuration. Conse4uently" -CPIPconnections established between any small office or home office computer and the Internet

connection sharing computer at the time of enabling Internet connection sharing are lost and

need to be reestablished.

5otes• =ou cannot modify the default configuration of Internet connection sharing. -his

includes items such as disabling the ,&CP allocator or modifying the range of private

IP addresses that are distributed" disabling the ,7S proxy" configuring a range of

 public IP addresses" or configuring inbound mappings. If you want to modify any of

these items" you must use networ% address translation.

•

If your home office users need to access a corporate networ% that is connected to theInternet by a tunnel server from an Internet connection sharing networ%" they need to

create a virtual private networ% connection to tunnel from the computer on the

Internet connection sharing networ% to the corporate tunnel server on the Internet. -he

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BP7 connection is authenticated and secure and creating the tunneled connection

allocates proper IP addresses" ,7S server addresses" and ?I7S server addresses for

the corporate networ%. 3or more information about creating a virtual private networ%

/BP70 connection.

32) What is #$,(remot access ser:ice).

3eote Access Service (3AS)?indows $888 Server remote access server/+AS0" part of the integrated +outing and +emote

Access service" connects remote or mobile wor%ers to organi'ation networ%s. +emote users

can wor% as if their computers are physically connected to the networ%. +emote access is

nothing but provide remote users to dial!in in our +AS server i.e. it allows inbound

connection to +AS server using dial!up connection and various auth. protocol li%e PAP" MS!

C&AP" SPAP" etc.

:sers run remote access software /,ail!up connection0 and initiate a connection to the remote

access server/+AS Server0. -he remote access server" which is a computer running ?indows

$888 Server and the +outing and +emote Access service" authenticates users and servicessessions until terminated by the user or networ% administrator. All services typically available

to a *A7!connected user /including file and print sharing" ?eb server access" and messaging0

are enabled by means of the remote access connection.

A remote access server running ?indows $888 provides two different types of remote access

connectivity

) Dial-up networkin",ial!up networ%ing is when a remote access client ma%es a non!permanent" dial!up

connection to a physical port on a remote access server by using the service of a

telecommunications provider such as analog phone /PS-70" IS,7" or .$9. -he best

example of dial!up networ%ing is that of a dial!up networ%ing client who dials the phone number of one of the ports of a remote access server.

,ial!up networ%ing over an analog phone or IS,7 is a direct physical connection

 between the dial!up networ%ing client and the dial!up networ%ing server. =ou can

encrypt data sent over the connection" but it is not re4uired.

$) Cirtual private networkin" (C*5)Birtual private networ%ing is the creation of secured" point!to!point connectionsacross a private networ% or a public networ% such as the Internet. A virtual private

networ%ing client uses special -CPIP!based protocols called tunnelin" protocols to

ma%e a virtual call to a virtual port on a virtual private networ%ing server. -he various

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tunnelling protcol used for BP7 are PP-P/Point to point tunneling protocol0" *$-P

/*ayer!$ tunneling protocol0. -he best example of virtual private networ%ing is that of 

a virtual private networ%ing client who ma%es a virtual private networ% connection to

a remote access server that is connected to the Internet. -he remote access server

answers the virtual call" authenticates the caller" and transfers data between the virtual

 private networ%ing client and the corporate networ%.

 33) What is 4+,(net*or6 operatin system) D

8etwor* Operating System $8OS'>et+ork /perating 0ystems are availle to support a C server ased net+ork. All Microsoft 4indo+s ased operating systems support peer-to-peer net+orking.0pecialied net+ork operating system (>/0) soft+are is required for a server-asednet+ork.

6"ampleni" G- A popular, roust operating system that comes in several forms from differentvendors.

Microsoft - 4in >-0erver, 4indo+s '@ 0erver

 Apple alk G - Mac /0

Dan Manager H Dan 0erver G- 3eveloped y Microsoft and :M that no longer very common.

3") What is topoloyD

8etwor* Topologies

)hat is Topology9t is physical +ay of communication, the configurations formed y the connections et+eendevices on a Docal Area >et+ork (DA>) or et+een t+o or more DA>*s.

t is important to make a distinction et+een a topology and an architecture. A topology isconcerned +ith the physical arrangement of the net+ork components.

here are three asic >et+ork opologies• The #us

• The Star 

• The 1ing

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+ 5hat is di"erence between 1$-RAM A*$ $$-RAM .

• 03 Ram is actually 03R 03RAM, and 33 Ram is actually 33R 03RAM,

though the former does not usually have the 03R in front of it. he letters03R and 33R stand for 0ingle 3ata Rate and 3oule 3ata Rate, and theletters 03RAM stand for 0ynchronous 3ynamic Random Access Memory.

he main difference et+een 03R and 33R memory is speed. here are alot of little differences, ut the main one (M7/) that affects the user is speedG33R can transfer data at roughly t+ice the speed of 03R. More speedy datarates I etter performance.

Just rememer, the motheroard you are using must include the appropriatechipset to support the different RAM types. hey are not interchangeale.

03R 03RAM comes in three main flavorsG C##, C%$$ and C%&&. 6achsuccessive numer refers to the us speed of the RAM in M7, thus C##runs at ## M7, C%$$ runs at %$$ M7, etc. 03R 03RAM has %#K pins atthe connector.

33R 03RAM has %K= pins at the connector, +hich is one reason you can*t 5ust use 33R instead of 03R, and comes in many different flavors1 C'%$$+hich runs at '## M7, C';$$ +hich runs at &&& M7, C&'$$ +hich runsat =$$ M7, etc. n order to kno+ +hich type of RAM you need, you mustkno+ +hat your motheroard supports

+ 5hat is di"erence between $$-RAM A*$ R$-RAM.

Short for  Rambus  DRAM  , a type of memory /,+AM0 developed by +ambus" Inc. ?hereas

the fastest current memory technologies used by PCs /S,+AM0 can deliver data at amaximum speed of about (88 M&'" +,+AM transfers data at up to K88 M&'.

In (LL" Intel announced that it would license the +ambus technology for use on its future

motherboards" thus ma%ing it the li%ely de facto standard for memory architectures. &owever"

a consortium of computer vendors is wor%ing on an alternative memory architecture called

Sync&ink %RAM (S&%RAM". 

+,+AM is already being used in place of  B+AM in some graphics accelerator boards. As of

late (LLL" Intel has been using +,+AM in its Pentium III eon processors and more recently

in its Pentium processors. Intel and +ambus are also wor%ing a new version of +,+AM"

called n%RAM " that will support data transfer speeds at up to ("688 M&'.

The entium 7 is nown to crave memory bandwidth above and over everything else.

The processor throws fits lie a baby when there is not enough memory bandwidth"

something which can often eep it from performing up to its potential. This was evident

when $ntel released their original i;74 chipset which allowed a entium 7 to be run with

conventional 325A, *hint: avoid lie the plague+.

/ften a 7 e0uipped with 325A," running at similar cloc speeds could not beat a at

1 8% in terms of performance? 225 alleviated the memory bandwidth bottlenec

somewhat with the i;742" delivering !.1 @s worth of bandwidth as opposed to the

1.; @s 325A, offered. That is still a far cry from the .! @s 525A, can supply

though" and today we're going to tae a loo at whether the i;4 B525A,B chipset is

that much faster then the i;742 B225B chipset.

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,any times readers have been writing in to asC BIs RDRAM really necessary for a

Pentium 4? B or maybe BI can't afford RDRAM, can I get by on DDR? B ,y personal favorite

isC BI'm a speed freak on a budget, but can I get good performance wit a P4!DDR

combo?  B.

Well today $ hope we set these 0uestions to rest and answer what has been on the minds

of manyC if 3piderman and 3uperman were in a battle who would win9 We also plan on

pitting RDRAM vs. DDR RAM and seeing which memory will be victorious # it is a battle

royal that even the great 3pidy can 'sense'.

There are a whole bunch of 225 chipsets now for the entium 7" but we're going to be

focusing on $ntel's own i;742. Why you as9 $ntel has always produced fast and very

stable chipsets *other then the i;!+ and the i;742 is no e&ception. @ased on the earlier

i;74 which was a very stable chipset in it's own" the i;742 only brings 225 capability to

the table and nothing else. Actually there are no real  differences between the i;74 or

i;742. 3ure there's an official revision difference" but basically the i;742 is the i;74 with

225 enabled.

The i;4 board we are testing with is the nice red ,3$ ;4 ro4 which has official

support for 7 ,8% based entium 7's using the 3ocet 7D; format. We had a few

i;742 based motherboards to choose from and eventually decided to eep it in the

family and test on the ,3$ ;74 <ltra. /ur testing processor is a entium 7 !. 8%

Williamette with !46E@ ! cache.

uestionG 5ust ought a computer that has 03RAM and no+ *m hearing that 33R and Ramusmemory are etter. 4hat are these ne+ types of memory and ho+ do they +orkL 3id uy the +rongthingL 7elp<

 Ans+erG 9ou heard right, 33R and Ramus 3RAM are t+o ne+ types of memory promising to makecomputers run faster. :ut efore +e discuss them, rela"< hey +ill >/ make 03RAM osolete in thenear future.

!irst, let*s start +ith a quick revie+. n the last fe+ years, 03RAM(synchronous 3RAM) has ecome the standard type of memory for Cs. he main reason for this isthat 03RAM is tied to the front-side us clock in your system. 03RAM and the us e"ecuteinstructions at the same time rather than one of them having to +ait for the other. As us speeds haveincreased eyond %$$M7, this has improved system performance.

1 S14733R (doule data rate) memory is the ne"t generation 03RAM. Dike

03RAM, 33R is synchronous +ith the system clock. he ig difference et+een 33R and 03RAMmemory is that 33R reads data on oth the rising and falling edges of the clock signal. 03RAM onlycarries information on the rising edge of a signal. :asically this allo+s the 33R module to transferdata t+ice as fast as 03RAM. !or e"ample, instead of a data rate of %&&M7, 33R memory transfersdata at '##M7.

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33R modules, like their 03RAM predecessors, are called 3MMs. hey use motheroard systemdesigns similar to those used y 03RAM1 ho+ever, 33R is not ack+ard compatile +ith 03RAM-designed motheroards. 33R memory supports oth 6CC (error correction code, typically used inservers) and non-parity (used on desktops2laptops.)

f your system or motheroard requires 33R, you can purchase the upgrades you need throughCrucial*s Memory 0elector .

1am-us 147Ramus memory (R3RAMN) is a revolutionary step from 03RAM. t*s a ne+ memory design +ithchanges to the us structure and ho+ signals are carried. Ramus memory sends less information onthe data us (+hich is %K its +ide as opposed to the standard &' or #= its) ut it sends data morefrequently. t also reads data on oth the rising and falling edges of the clock signal, as 33R does. Asa result, Ramus memory is ale to achieve effective data transfer speeds of K$$M7 and higher.

 Another difference +ith Ramus memory is that all memory slots in the motheroard must epopulated. 6ven if all the memory is contained in a single module, the 8unused8 sockets must epopulated +ith a C:, kno+n as a continuity module, to complete the circuit.

Ramus 3RAM modules are kno+n as RMM modules (Ramus inline memory modules). Ramusmemory supports oth 6CC and non-6CC applications.

+roduction 5hallenges

/ne of the challenges Ramus memory currently faces is that it is e"pensive to produce compared to03RAM and 33R. Ramus memory is proprietary technology of Ramus nc. Manufacturers that+ant to produce it are required to pay a royalty to Ramus nc., +hereas 33R designs are openarchitecture. /ther cost factors for Ramus memory include additional module manufacturing andtesting processes and a larger die sie. Ramus die (chips) are much larger than 03RAM or 33R die.hat means fe+er parts can e produced on a +afer.

+erformance>o+ for the million-dollar questionG 7o+ do 33R and Ramus memory compare performance +iseL0orry, kno+ you don*t +ant to hear this that depends. :oth technologies have their o+n ardentsupporters and +e have seen several different enchmarks to date that provide conflicting results.

/n the surface, it seems simpleG 3ata flo+ at K$$M7 is faster than data flo+ at '##M7, rightL

nfortunately, it isn*t that simple. 4hile Ramus modules may have the aility to transfer data faster, itappears to have higher latency (the amount of time you have to +ait until data flo+s) than that of a33R system. n other +ords, the first data item transferred in a Ramus transaction takes longer toinitiate than the first data item moved in a 33R system. his is due in part to ho+ the systems areconstructed.

n a 33R or 03RAM system, each 3MM is connected, individually and in parallel, to the data us. 0o+hether you have a single 3MM or multiple 3MMs, the amount of time it takes to initiate a datatransfer is effectively unchanged.

n a Ramus system, RMM modules are connected to the us in a series. he first data itemtransferred must pass through each RMM module efore it reaches the us. his makes for a muchlonger distance for the signal to travel. he result is higher latency. hat*s not necessarily a prolem in

an environment +here data transactions involve lengthy streams of data, such as gaming. :ut it canecome an issue in environments +here many small transactions are initiated regularly, such as aserver.

o further e"plain, here*s an e"ample that +e can all relate to driving your car to the store. 9ou cantake the roundaout free+ay and drive '$ miles at ;$ M7. /r, you can take a more direct route anddrive 5ust ? miles at ?$ M7. 9ou might go faster on the free+ay ut you*ll get to the store (MemoryController) faster on the straight-line route.

Loo*ing to the Future0o +hich technology +ill ecome the memory of choice for the computer industryL hat proaly+on*t e clear until sometime in the near future. 7o+ever, it really doesn*t matter to a certain e"tent.

Eenerally speaking, motheroards are uilt to support one type of memory. 9ou cannot mi" andmatch more than one type of 03RAM, 33R, or Ramus memory on the same motheroard in anysystem. hey +ill not function and +ill not even fit in the same sockets. he right type of memory touse is the one that your motheroard takes< And no matter +hat type of memory you use, more is

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typically etter. A memory upgrade is still one of the most cost-effective +ays to improve systemperformance.

 At this point in time, the market for 33R and Ramus memory is relatively small. 7o+ever, it isgro+ing. Crucial currently offers 33R and +ill offer other ne+ technologies as the market dictates.

35) What is peer to peer net*or6.

 A net+ork in +hich there are no dedicated servers among the computers. All computers shareresources such as files and printers therefore acting as oth client and server.

 A communication net+ork +ithout a dedicated server. 6ach computer in the net+ork can act as aclient and a server. Any computer can access files on any other computer in the net+ork.

5indows Peer-to-Peer *etworking

?indows Peer!to!Peer 7etwor%ing is an operating system component

that enables the creation of new peer!to!peer /P$P0 applications for

computers running ?indows P /Service Pac% ( and later0. P$P

applications can utili'e the powerful personal computers that exist at

the edge of the Internet to create exciting" distributed experiences. P$Pnetwor%ing can also allow existing applications to wor% together in

new and useful ways.

'Microsofts peer-to-peer technology, integrated in )orel *rafigo 2, allo$s real-time

collaboration $ith anyone across the table or around the $orld, and has the ability to

radically impro!e the $ay professionals create and echange graphical content in a mobile

 setting'  NJraham )rown" Bice President" Software ,evelopment" Corel Corporation

peer-to-peer architectureften referred to simply as peertopeer  or abbreviated P!P a type ofnetwork in which each workstation has e9uivalent capabilities andresponsibilities. !his di"ers from client&server architectures in which somecomputers are dedicated to serving the others. Peer-to-peer networks aregenerally simpler but they usually do not o"er the same performance underheavy loads.

38) What is C'+, D

1hort for complementary metal o "ide semiconductor . Pronounced seemoss%M1 is a widely used type of semiconductor. %M1 semiconductors use

both *M1 (negative polarity and PM1 (positive polarity circuits. 1inceonly one of the circuit types is on at any given time %M1 chips re9uire lesspower than chips using ,ust one type of transistor. !his makes themparticularly attractive for use in battery-powered devices such as portable computers. Personal computers also contain a small amount of battery-powered %M1 memory to hold the date time and system setup parameters.

 !he %M1 or %omplementary Metal ;ide 1emiconductor is an on-boardsemiconductor chip. 5hich re9uires very low power generated from varioustypes of %M1 batteries which are shown below. !his chip is used to storeimportant system information and con4guration settings while the computeris o" and on.

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Types o1 &!8S atteries - -he following is a listing of the types of batteries found in

computer to power the CM<S memory. -he most common type of battery is the Coin cell

 battery /*ithium )attery0 the coin cell battery is the si'e of a dime" as shown below.

Li1e tie o1 a &!8S attery - -he standard life time of a CM<S battery is around (8

=ears" however this amount of time can change depending on the use and environment that

the computer resides.

In CM<S /)omplementary Metal-+ide Semiconductor 0 technology" both 7!type and P!type

transistors are used to reali'e logic functions. -oday" CM<S technology is the dominant

semiconductor technology for microprocessors" memories and application specific integrated

circuits /ASICs0. -he main advantage of CM<S over 7M<S and bipolar technology is the

much smaller power dissipation. :nli%e 7M<S or bipolar circuits" a CM<S circuit has

almost no static power dissipation. Power is only dissipated in case the circuit actually

switches. -his allows to integrate many more CM<S gates on an IC than in 7M<S or bipolar 

technology" resulting in much better performance.

-he following applets demonstrate the 7!type and P!type transistors used in CM<Stechnology" the basic CM<S inverter" 7A7, and 7<+ gates" and an A<I#$ complex gate.

3inally" it demonstrates the CM<S transmission!gate and a transmisson!gate ,!latch.

-he first applet illustrates the function of both 7!type and P!type M<S transistors.

Clic% on the source and gate contacts of the transistors to toggle the corresponding voltage

levels and watch the resulting output value on the drain contacts. -he applet uses colors to

display the different voltages.

• A logical ( corresponding to electrical level BCC /typical values for current

technolgies are O9B or O#.#B0 is shown in red"

• a logical 8 /corresponding to 8B or J7,0 in blue.

• A floating wire /not connected to either BCC or J7,0 is shown in orange.

How #IOS )or*s

/ne of the most common uses of !lash memory is for the -asic input;output system of your computer,

commonly kno+n as the :/0 (pronounced 8ye-ose8)./n virtually every computer availale, the :/0 makessure all the other chips, hard drives, ports and Cfunction together.

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6very desktop and laptop computer in common use today contains a microprocessor as its central processing unit. he microprocessor is the hardware component. oget its +ork done, the microprocessor e"ecutes a set of instructions kno+n assoftware (see 7o+ Microprocessors 4ork for details). 9ou are proaly very familiar +ith t+o different types of soft+areG

• he operating system - he operating system provides a set of services for

the applications running on your computer, and it also provides the

fundamental user interface for your computer. 4indo+s FK and Dinu" aree"amples of operating systems. (0ee 7o+ /perating 0ystems 4ork for lots of details.)

• he applications - Applications are pieces of soft+are that are programmedto perform specific tasks. /n your computer right no+ you proaly have aro+ser application, a +ord processing application, an e-mail application andso on. 9ou can also uy ne+ applications and install them.

t turns out that the :/0 is the third type of soft+are your computer needs tooperate successfully. n this article, you*ll learn all aout :/0 -- +hat it does, ho+ to

configure it and +hat to do if your :/0 needs updating.

Configuring :/0n the previous list, you sa+ that the :/0 checks the CM/0 0etup for customsettings. 7ere*s +hat you do to change those settings.

o enter the CM/0 0etup, you must press a certain key or comination of keysduring the initial startup se3uence. Most systems use 86sc,8 83el,8 8!%,8 8!',8 8Ctrl-6sc8 or 8Ctrl-Alt-6sc8 to enter setup. here is usually a line of te"t at the ottom ofthe display that tells you 8ress OOO to 6nter 0etup.8

/nce you have entered setup, you +ill see a set of te"t screens +ith a numer ofoptions. 0ome of these are standard, +hile others vary according to the :/0manufacturer. Common options includeG

• System Time;ate - 0et the system time and date

• #oot Se3uence - he order that :/0 +ill try to load the operating system

• +lug and +lay - A standard for auto-detecting connected devices1 should eset to 89es8 if your computer and operating system oth support it

• 7ouse;<ey-oard - 86nale >um Dock,8 86nale the @eyoard,8 8Auto-3etectMouse8...

• ri"e 5onfiguration - Configure hard drives, C3-R/M and floppy drives

• 7emory - 3irect the :/0 to shado+ to a specific memory address

• Security - 0et a pass+ord for accessing the computer

• +ower 7anagement - 0elect +hether to use po+er management, as +ell as

set the amount of time for stand-y and suspend 

• Exit - 0ave your changes, discard your changes or restore default settings

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57OS Setup

:e very careful +hen making changes to setup. ncorrect settings may keep your

computer from ooting. 4hen you are finished +ith your changes, you shouldchoose 80ave Changes8 and e"it. he :/0 +ill then restart your computer so thatthe ne+ settings take effect.

he :/0 uses 57OS technology to save any changes made to the computer*ssettings. 4ith this technology, a small lithium or >i-Cad attery can supply enoughpo+er to keep the data for years. n fact, some of the ne+er chips have a %$-year,tiny lithium attery uilt right into the CM/0 chip<

pdating 9our :/0/ccasionally, a computer +ill need to have its :/0 updated. his is especially true

of older machines. As ne+ devices and standards arise, the :/0 needs to changein order to understand the ne+ hard+are. 0ince the :/0 is stored in some form ofR/M, changing it is a it harder than upgrading most other types of soft+are.

o change the :/0 itself, you*ll proaly need a special program from the computeror :/0 manufacturer. Dook at the :/0 revision and date information displayed onsystem startup or check +ith your computer manufacturer to find out +hat type of:/0 you have. hen go to the :/0 manufacturer*s 4e site to see if an upgrade isavailale. 3o+nload the upgrade and the utility program needed to install it.0ometimes the utility and update are comined in a single file to do+nload. Copy theprogram, along +ith the :/0 update, onto a floppy disk. Restart your computer +ith

the floppy disk in the drive, and the program erases the old :/0 and +rites the ne+one. 9ou can find a :/0 4iard that +ill check your :/0 at :/0 pgrades. 

Ma5or :/0 manufacturers includeG

•  American Megatrends nc. (AM) 

• hoeni" echnologies 

•  ADi 

• 4inond 

 As +ith changes to the CM/0 0etup, e careful +hen upgrading your :/0. Makesure you are upgrading to a version that is compatile +ith your computer system./ther+ise, you could corrupt the :/0, +hich means you +on*t e ale to oot your

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computer. f in dout, check +ith your computer manufacturer to e sure you need toupgrade.

:ooting the Computer 4henever you turn on your computer, the first thing you see is the :/0 soft+aredoing its thing. /n many machines, the :/0 displays te"t descriing things like theamount of memory installed in your computer, the type of hard disk and so on. tturns out that, during this oot sequence, the :/0 is doing a remarkale amount of

+ork to get your computer ready to run. his section riefly descries some of thoseactivities for a typical C.

 After checking the CM/0 0etup and loading the interrupt handlers, the :/0determines +hether the video card is operational. Most video cards have a miniature:/0 of their o+n that initialies the memory and graphics processor on the card. fthey do not, there is usually video driver information on another R/M on themotheroard that the :/0 can load.

>e"t, the :/0 checks to see if this is a cold -oot or a re-oot. t does this ychecking the value at memory address $$$$G$=;'. A value of %'&=h indicates areoot, and the :/0 skips the rest of /0. Anything else is considered a coldoot.

f it is a cold oot, the :/0 verifies RAM y performing a read2+rite test of eachmemory address. t checks the 02' ports or 0: ports for a keyoard and a mouse.t looks for a peripheral component interconnect (C) us and, if it finds one,checks all the C cards. f the :/0 finds any errors during the /0, it +ill notifyyou y a series of eeps or a te"t message displayed on the screen. An error at thispoint is almost al+ays a hard+are prolem.

he :/0 then displays some details aout your system. his typically includesinformation aoutG

• he processor  

• he floppy drive and hard drive 

• Memory 

• :/0 revision and date

• 3isplay

 Any special drivers, such as the ones for small computer system interface (0C0)

adapters, are loaded from the adapter, and the :/0 displays the information. he:/0 then looks at the sequence of storage devices identified as -oot devices in theCM/0 0etup. 8:oot8 is short for 8ootstrap,8 as in the old phrase, 8Dift yourself up yyour ootstraps.8 :oot refers to the process of launching the operating system. he:/0 +ill try to initiate the oot sequence from the first device. f the :/0 does notfind a device, it +ill try the ne"t device in the list. f it does not find the proper files ona device, the startup process +ill halt. f you have ever left a floppy disk in the drive+hen you restarted your computer, you have proaly seen this message.

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This is the message you get if a floppy dis* is in the dri"ewhen you restart your computer&

he :/0 has tried to oot the computer off of the floppy disk left in the drive. 0inceit did not find the correct system files, it could not continue. /f course, this is an easyfi". 0imply pop out the disk and press a key to continue.

' ) )hat is the difference -etween a +entium and a 5eleron processor9

7ere are the most important similarities and differences et+een the entium = andthe Celeron chips coming out todayG

• 5ore - he Celeron chip is ased on a entium = core.

• 5ache - Celeron chips have less cache memory than entium = chips do. A

Celeron might have %'K kiloytes of D' cache, +hile a entium = can havefour times that. he amount of D' cache memory can have a ig effect onperformance.

• 5loc* speed - ntel manufactures the entium = chips to run at a higher clockspeed than Celeron chips. he fastest entium = might e #$ percent fasterthan the fastest Celeron.

• #us speed - here are differences in the ma"imum us speeds that the

processors allo+. entium =s tend to e aout &$ percent faster thanCelerons.

4hen you sort all this out and compare the t+o chips side y side, it turns out that aCeleron and a entium = chip running at the same speed are different easts. hesmaller D' cache sie and slo+er us speeds can mean serious performancedifferences depending on +hat you +ant to do +ith your computer . f all you do ischeck e-mail and ro+se the 4e, the Celeron is fine, and the price difference cansave you a lot of money. f you +ant the fastest machine you can uy, then you needto go +ith the entium = to get the highest clock speeds and the fastest system us.

,=' How 7icroprocessors )or* 9f you have een shopping for a computer , then you have heard the +ord 8cache.8Modern computers have oth D% and D' caches. 9ou may also have gotten adviceon the topic from +ell-meaning friends, perhaps something like 83on*t uy thatCeleron chip, it doesn*t have any cache in it<8

t turns out that caching is an important computer-science process that appears onevery computer in a variety of forms. here are memory caches, hard+are andsoft+are disk caches, page caches and more. Birtual memory is even a form ofcaching. n this article, +e +ill e"plore caching so you can understand +hy it is soimportant.

RAM and R/Mhe previous section talked aout the address and data uses, as +ell as the R3and 4R lines. hese uses and lines connect either to RAM or R/M -- generallyoth. n our sample microprocessor, +e have an address us K its +ide and a data

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us K its +ide. hat means that the microprocessor can address ('K) '?# ytes ofmemory, and it can read or +rite K its of the memory at a time. Det*s assume thatthis simple microprocessor has %'K ytes of R/M starting at address $ and %'Kytes of RAM starting at address %'K.

1O7 chip

R/M stands for read-only memory. A R/M chip is programmed +ith a permanentcollection of pre-set ytes. he address us tells theR/M chip +hich yte to get and place on the data us.4hen the R3 line changes state, the R/M chippresents the selected yte onto the data us.

RAM stands for random-access memory. RAM containsytes of information, and the microprocessor can reador +rite to those ytes depending on +hether the R3 or 4R line is signaled. /ne prolem +ith today*s RAMchips is that they forget everything once the po+er  goes

off. hat is +hy the computer needs R/M.

:y the +ay, nearly all computers contain some amount of R/M (it is possile tocreate a simple computer that contains no RAM -- many microcontrollers do this yplacing a handful of RAM ytes on the processor chip itself -- ut generallyimpossile to create one that contains no R/M). /n a C, the R/M is called the:/0 (:asic nput2/utput 0ystem). 4hen the microprocessor starts, it eginse"ecuting instructions it finds in the :/0. he :/0 instructions do things like testthe hard+are in the machine, and then it goes to the hard disk to fetch the -ootsector  (see 7o+ 7ard 3isks 4ork for details). his oot sector is another smallprogram, and the :/0 stores it in RAM after reading it off the disk. he

microprocessor then egins e"ecuting the oot sector*s instructions from RAM. heoot sector program +ill tell the microprocessor to fetch something else from thehard disk into RAM, +hich the microprocessor then e"ecutes, and so on. his is ho+the microprocessor loads and e"ecutes the entire operating system.

,%' How Ethernet )or*s

n today*s usiness +orld, reliale and efficient access to information has ecome animportant asset in the quest to achieve a competitive advantage. !ile cainets andmountains of papers have given +ay to computers that store and manageinformation electronically. Co+orkers thousands of miles apart can share informationinstantaneously, 5ust as hundreds of +orkers in a single location can simultaneouslyrevie+ research data maintained online.

Computer net+orking technologies are the glue that inds these elements together.he pulic nternet allo+s usinesses around the +orld to share information +ith

147 chip

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each other and their customers. he gloal computer net+ork kno+n as the 4orld4ide 4e provides services that let consumers uy ooks, clothes, and even carsonline, or auction those same items off +hen no longer +anted.

n this article, +e +ill take a very close look at net+orking, and in particular the6thernet net+orking standard, so you can understand the actual mechanics of ho+all of these computers connect to one another.

4hy >et+orkL8etwor*ing allo+s one computer to send information to and receive informationfrom another. 4e may not al+ays e a+are of the numerous times +e accessinformation on computer net+orks. Certainly the nternet is the most conspicuouse"ample of computer net+orking, linking millions of computers around the +orld, utsmaller net+orks play a role in information access on a daily asis. Many pulicliraries have replaced their card catalogs +ith computer terminals that allo+ patronsto search for ooks far more quickly and easily. Airports have numerous screensdisplaying information regarding arriving and departing flights. Many retail storesfeature specialied computers that handle point-of-sale transactions. n each ofthese cases, net+orking allo+s many different devices in multiple locations to accessa shared repository of data.

:efore getting into the details of a net+orking standard like 6thernet, +e must first

understand some asic terms and classifications that descrie and differentiatenet+ork technologies -- so let*s get started<

How Internet Search Engines )or*he good ne+s aout the nternet and its most visile component, the 4orld 4ide4e, is that there are hundreds of millions of pages availale, +aiting to presentinformation on an amaing variety of topics. he ad ne+s aout the nternet is thatthere are hundreds of millions of pages availale, most of them titled according to

the +him of their author, almost all of them sitting on servers +ith cryptic names.4hen you need to kno+ aout a particular su5ect, ho+ do you kno+ +hich pages toreadL f you*re like most people, you visit an Internet search engine.

nternet search engines are special sites on the 4e that are designed to helppeople find information stored on other sites. here are differences in the +aysvarious search engines +ork, ut they all perform three asic tasksG

• hey search the nternet -- or select pieces of the nternet -- ased on

important +ords.

• hey keep an inde" of the +ords they find, and +here they find them.

• hey allo+ users to look for +ords or cominations of +ords found in thatinde".

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6arly search engines held an inde" of a fe+ hundred thousand pages anddocuments, and received maye one or t+o thousand inquiries each day. oday, atop search engine +ill inde" hundreds of millions of pages, and respond to tens ofmillions of queries per day. n this article, +e*ll tell you ho+ these ma5or tasks areperformed, and ho+ nternet search engines put the pieces together in order to letyou find the information you need on the 4e.

How Internet Infrastructure )or*s

/ne of the greatest things aout the nternet is that noody really o+ns it. t is agloal collection of net+orks, oth ig and small. hese net+orks connect together inmany different +ays to form the single entity that +e kno+ as the Internet. n fact,the very name comes from this idea of interconnected net+orks.

0ince its eginning in %F#F, the nternet has gro+n from four host computer systemsto tens of millions. 7o+ever, 5ust ecause noody o+ns the nternet, it doesn*t meanit is not monitored and maintained in different +ays. he nternet 0ociety, a non-profit group estalished in %FF', oversees the formation of the policies and protocolsthat define ho+ +e use and interact +ith the nternet.

n this article, you +ill learn aout the asic underlying structure of the nternet. 9ou+ill learn aout domain name servers, net+ork access points and ackones. :utfirst you +ill learn aout ho+ your computer connects to others.

Collision 3etectionCarrier-sense multiple access gives us a good start in regulating our conversation,ut there is one scenario +e still need to address. DetPs go ack to our dinner taleanalogy and imagine that there is a momentary lull in the conversation. 9ou and oth have something +e +ould like to add, and +e oth 8sense the carrier8 ased onthe silence, so +e egin speaking at appro"imately the same time. n 6thernetterminology, a collision occurs +hen +e oth spoke at once.

n our conversation, +e can handle this situation gracefully. 4e oth hear the otherspeak at the same time +e are speaking, so +e can stop to give the other person achance to go on. 6thernet nodes also listen to the medium +hile they transmit to

ensure that they are the only station transmitting at that time. f the stations hear their o+n transmission returning in a garled form, as +ould happen if some other stationhad egun to transmit its o+n message at the same time, then they kno+ that acollision occurred. A single 6thernet segment is sometimes called a collision

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domain ecause no t+o stations on the segment can transmit at the same time+ithout causing a collision. 4hen stations detect a collision, they ceasetransmission, +ait a random amount of time, and attempt to transmit +hen theyagain detect silence on the medium.

he random pause and retry is an important part of the protocol. f t+o stationscollide +hen transmitting once, then oth +ill need to transmit again. At the ne"tappropriate chance to transmit, oth stations involved +ith the previous collision +ill

have data ready to transmit. f they transmitted again at the first opportunity, they+ould most likely collide again and again indefinitely. nstead, the random delaymakes it unlikely that any t+o stations +ill collide more than a fe+ times in a ro+.

How 5omputer >iruses )or*Computer viruses are mysterious and gra our attention. /n the one hand, virusessho+ us ho+ vulnerale +e are. A properly engineered virus can have an amaingeffect on the +orld+ide nternet. /n the other hand, they sho+ ho+ sophisticatedand interconnected human eings have ecome.

!or e"ample, the thing making ig ne+s right no+ is the Mydoom +orm, +hiche"perts estimate infected appro"imately a quarter-million computers in a single day(imes /nline). :ack in March %FFF, the Melissa virus +as so po+erful that it forcedMicrosoft and a numer of other very large companies to completely turn off their e-mail systems until the virus could e contained. he D/B69/ virus in '$$$ had asimilarly devastating effect. hat*s pretty impressive +hen you consider that theMelissa and D/B69/ viruses are incredily simple.

n this article, +e +ill discuss viruses -- oth 8traditional8 viruses and the ne+er e-mail viruses -- so that you can learn ho+ they +ork and also understand ho+ toprotect yourself. Biruses in general are on the +ane, ut occasionally a person findsa ne+ +ay to create one, and that*s +hen they make the ne+s.

"2) ell me about ntbac6up type D

1)normal bac6up

Bac6s up all selecte! Ales an! mar6s each Ale as bac6e! up.

2)copy bac6up

Bac6s up all selecte! Ales but !oes not mar6 any as bac6e!

up.

3)%i0erential

Bac6s up selecte! Ales only i they ha:e not been bac6e! upor ha:e been chane! but !oes not mar6 any as bac6e! up.

")IncrementalBac6s up selecte! Ales only i they ha:e not been bac6e! up or ha:e been chane! an! mar6s them as bac6e! up.

)%aily77777777777777777777Bac6s up only Ales *hich ha:e been chane! to!ay but

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!oes not mar6 them as bac6e! up.

"3) %i0erence #ee!it an! ree!t32

4hen 4indo+s F? came out, the registry +as one of the ig ne+ features offered +ith thatoperating system. nstead of storing system and application configuration information in a +holesle+ of .> files scattered across the hard drive, the registry moved all of that information intoone place. @no+ing ho+ to plo+ through the registry is proaly something any decent 4indo+s>2 4indo+s '$$$ sysadmin should kno+ aout.

/ne of the not-very-+ell-e"plained quirks aout editing the registry is that there are t+o toolsavailale y default for doing this in > and '@G R6E63 and R6E63&'. he t+o have somemarked differences that need to e kept in mind.

R6E63 is asically a copy of the original registry-editing utility found in 4indo+s F?, and iskept around in other versions of 4indo+s for the sake of ack+ard compatiility. R6E63&', onthe other hand, +as only shipped +ith >, '@ and Q. he main difference et+een the t+o isthat R6E63&' allo+s you to set and clear permissions in the registry, +hile R6E63 doesn*t.

6ach key in the registry in > and '@ (and Q, of course) has an access control list or ACD -- ine"actly the same manner that files and folders on an >!0 volume have ACDs. he reason forthis applies as it does on files and foldersG to allo+ or deny access to certain o5ects ased on agiven user*s credentials. his +ay a given user could e provided access to one particularsutree of the registry, ut not another.

o edit the permissions for a particular key in R6E63&', right-click on the key in the left-handpane and select ermissions. A dialog o" similar to the kind used to set permissions on files andfolders +ill come up. his lets you set asic or advanced permissions, and also set or reset theinheritaility of those permissions on any sukeys of the key you*re editing. 9ou may need toclear permissions for a sukey if you are, for instance, trying to uninstall an application fromanother user account and need to purge the keys as an administrator to do it.

Windows NT 4.0 and Windows 2000 Regedit.exe

5egedit.e&e is included with Windows =T 7. and Windows ! primarilyfor its search capability. ou can use 5egedit.e&e to mae changes in theWindows =T 7. and Windows ! registry" but you cannot use it to viewor edit all functions or data types on Windows =T 7. and Win!.The following limitations e&ist in the 5egedit.e&e version that is includedwith Windows =T 7. and Windows !:

G ou cannot set the security for registry eys.

G ou cannot view" edit" or search the value data types5(H(IA=2H3J and 5(H,<T$H3J. $f you try to view a5(H(IA=2H3J value" 5egedit.e&e displays it as a binary datatype. $f you try to edit either of these data types" 5egedit.e&e savesit as 5(H3J" and the data type no longer performs its intendedfunction.

G ou cannot save or restore eys as hive files.

,icrosoft recommends that you use 5egedit.e&e only for its searchcapabilities on a Windows =T 7.#based or Windows !#basedcomputer.

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Regedt32.exe

5egedt!.e&e is the configuration editor for Windows =T 7. and Windows!. 5egedt!.e&e is used tomodify the Windows =T configurationdatabase" or the Windows =Tregistry. This editor allows you to view ormodify the Windows =T registry.The editor provides views of windows thatrepresent sections of theregistry" named hives. (ach window displays two

sections. /n the leftside" there are folders that represent registry eys./n the right side"there are the values associated with the selectedregistry ey. 5egedt! isa powerful tool" and you must use it withe&treme caution when you changeregistry values. ,issing or incorrectvalues in the registry can mae theWindows installation unusable.

Note <nlie 5egedit.e&e" 5egedt!.e&e does not support importing ande&porting registration entries *.reg+ files.

77+ In *hich Ale the !irectory an! inormation store is sa:e!

e!b 7 exchane !atabase

(&change 3erver is a comple& beast" to say the least. $t's >ust a fact of life that we can'tescape and if one is to wor with (&change it's >ust best to accept it and move on. As easy as

(&change ! is to wor with" it's still not the easiest or most pleasurable thing to do on a3aturday afternoon *or any day for that matter+. <nderstanding the underlying processes and

construction of (&change can go a long way towards increasing your happiness factor#which

is" after all" the only thing that really matters in life?

The Databases(verything these days re0uires a database of some sort. The $nternal 5evenue 3ervice" Active

2irectory" even the local supermaret#they all use a database. 2atabases are great" but they

are not always easy to understand. Figure 1 shows an e&ample of what the (&change 3erverdatabase loos lie.

Figure 1 - The current database (from Chapter 28 of the Exchange 2000 Server 

esource !it"#

As you can see from Figure 1" there are actually three files that mae up a current (&change

database for a storage group" as e&plained below.

• The .edb file contains all the folders" tables and inde&es for messaging data and ,A$

messages and attachments.

• The .stm file *new to (&change !+ contains $nternet content in its native format.

• The .log files *transaction logs+ maintains a record of every message stored in a

storage group and provides fault tolerance in the event that a database must berestored. (&change ! log files are always 4,@ in si%e *4"!4!";; bytes+ and if

not" then they are damaged. (ach storage group also reserves to log files" 5es1.log

and 5es!.log that are placeholders for e&tra dis place that can be used if the serviceruns out of space.

The Che!"oint File$n addition to the files previously mentioned" there is one other file of special note that plays

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a big role in eeping your (&change 3erver database in order. The checpoint file *edb.ch+tracs which entries in the transaction log files have already been recorded" and thus which

ones will need to be replayed during a restoration situation. The checpoint file thus speeds

up recovery by telling the (3( e&actly which log file entries need to be replayed and which donot#thus preventing e&tra writing during the restoration process.

Ci#$la# %ogging

Typically" when a log file is filled" (&change renames it and moves on to another" fresh logfile. $n this way" log files are not erased and thus continue to use space in 4,@ increments.

As the number of transactions grows" a set of log files is created. $f a database fails" thetransactions can be recovered by restoring the data from the log files. When circular logging

is enabled" the first log file is overwritten and reused after the data that it contains has beenwritten to the database. -ircular logging is available to you" but is disabled by default. 3hould

you enable circular logging" you cannot recover anything more recent than the last fullbacup. For this reason" circular logging is not normally recommended for use in a mission#

critical production environment" with the possible e&ception of the ublic folder that willhouse your ==T news feeds" where log file sets are not re0uired.

The Che!s$mThe concept of a checsum is not a new one. -hecsums have been used for years to enabledetermination of file validity. (&change 3erver maes use of checsums to verify the validity

of the .edb files. (very .edb file is made up 7#E@ pages and the integrity of each page is

verified through a checsum and a 7#byte page number in the header of the database page./n each page in the database" the first ;! bytes contain the header information" which

contains flags for the type of page and information about what ind of data the page

contains. When the pages are read out of the database" they are compared for the correctpage number and for the checsum. The checsum is calculated to ensure that the page

being read is undamaged. $f damage is detected" an error is returned" the database isstopped and an event is written in the to the event logs" thus ensuring that the database is

operating with optimal integrity.

&the# 'm"o#tant FilesAlthough not part of the actual (&change database" the following two additional files may also

be present on an (&change 3ever:

•

The .s#s files that permit bacwards compatibility with (&change 4.4 3erver byemulating an (&change 4.4 directory service. This will only be present if the (&change

A2- is installed and you then configure a 3ite 5eplication 3erver.

• The .!ms files which provide security and encryption services. This will only be

present on (&change servers that have the E,3 installed.

(eah) *$t +o What,/E" so now we've got an idea of what maes up the (&change 3erver databases and what

special features they have. @ut who cares9 What good does this do9 Well:when $ alludedearlier to woring with (&change on a 3aturday afternoon" that seemed lie a good time for

the (&change 3erver to crater and you find yourself in the midst of restoring it so thatbusiness can go on as normal on ,onday. That's why you've got that pager after all" isn't it9

$ discussed (&change recovery in another article" 2isaster 5ecovery" but $ never really gotinto detail about setting up the bacup system or how the restore action occurs.

@efore we can get to the process of performing the bacup" and more specifically" how(&change handles a bacup re0uest" we need to understand what each type of bacup will do

for.

*a!$" T-"esThere are five basic types of bacups that can be performed using ntbacup.e&e" but only

four of those apply to (&change 3erver. They are summari%ed below:

• Full *normal+ bacups bacup the entire Web 3torage 3ystem and the (&change log

files. All transaction logs that contain transactions already committed to the database

are deleted. 5estoring from a full bacup re0uired only the full bacup media. Fullbacups are the preferred means of bacing up the (&change databases.

• -opy bacups act the same of full bacups with the e&ception that the transaction log

files are not deleted. ou can perform a copy bacup at any time without disturbing

the status of any other type of bacup.

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• $ncremental bacups bacup all log files prior to the checpoint log and then delete

them. Additionally" incremental bacups bac up all transaction log files and deletethe log files that contain transactions that have been committed to the database.

5estoring from an incremental bacup re0uires that you have the last full bacup andeach subse0uent incremental bacup. $f one incremental bacup is damaged" you

cannot restore any incremental bacups made after that point as one damaged logfile prevents replaying subse0uent log files. $t is critical that all incremental bacups

be restored prior to starting log file replay to prevent losing data or damaging thedatabase.

• 2ifferential bacups bacup all log files prior to the checpoint file" but does not

delete them. 2ue to this" each bacup file will be larger in si%e than the previous file.

5estoring from a differential bacup re0uires that you have the last full bacup andthe last differential bacup. 2ifferential bacups are the second most preferred

method of performing bacups" after full bacups.

The *a!$" #oessWhen the bacup process is started *using the ntbacup.e&e+" the Web 3torage 3ystem

informs the (3( that it is entering a bacup mode and a patch file is created for eachdatabase in the bacup *if for a full bacup" otherwise a patch file is not created+. The

currently open log file is closed out and renames and new log file is opened at this time as

well. This indicates the point at which the (3( can truncate the logs after the bacup processhas completed. Figure ! illustrates the bacup process.

Figure 2 - The bac$up process (from Chapter 28 of the Exchange 2000 Server 

esource !it"#

When the bacup is started" the agent re0uests that the database read and se0uence all

database pages from the (3(. As the database reads the pages" the (3( verifies themthrough a checsum to ensure that they are valid. $f they are invalid" the bacup stops to

prevent the storage of damaged data. After the bacup is complete and all the pages areread" the bacup copies the logs and patch files to the bacup set. The log files are then

truncated or deleted at the point when the new generation started at the beginning of thebacup. The bacup set closes" the (3( enters normal mode" and the bacup is complete.

The preceding description assumed that you were performing an online bacup *databasesonline at the time of bacup+" which is the preferred mode since it allows the databases to

remain online and usable. ou can" however" perform an offline bacup by taing thedatabases offline. /ffline bacups are always full bacups as the databases are dismounted

and therefore not available for writing by networ clients.

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/f course" the bacup is >ust the first half of the solution. @eing able to restore the datawould be nice as well.

The Resto#ation #oessThe restoration process pretty much mirrors the bacup process" but obviously in reverse.

@efore you can perform a restoration" you will need to tae the database *or storage group+offline by dismounting it. When the restoration process begins" the (3( enters restore mode.

The bacup agent copies the database from the bacup media to the target location. The

associated log and patch files are copied to a temporary location *as specified by the bacup

operator+ so they aren't saved to the same location as current files in the (&change orroduction 2atabase directory. 3hould the log and patch files happen to be places in thesame location" log files can be overwritten which will cause corruption of the database. After

the files are restored" a special instance of the (3( starts for the specific purpose of restoringthe database. $t applies the patch file and log files to bring the database up to date. After the

restore is complete" the log and patch files are deleted from the temporary location and thestorage group is mounted and made available for use. Figure summari%es the restoration

process.

Figure % - The restoration process (from Chapter 28 of the Exchange 2000 Server 

esource !it"#

&ne %ast Thing/A point worth mentioning is that the version of ntbacup.e&e that ships with Windows !*4..!1D!.1+ cannot be used to perform (&change ! 3erver bacups. ou will need to

have version 4..!1K4.111D or later installed on your system. Figure 7 shows the version ofntbacup.e&e that ships with Windows ! *unmodified+ and Figure 4 shows the versionthat comes with 3ervice ac !.

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Figure & - ntbac$up#exe origina' fi'e#

Figure - ntbac$up#exe in Service )ac$ 2#

W#a"1"/As we've seen" the (&change 3erver database arrangement is a fairly comple& one" although

one that has safeguards built into it to minimi%e damage and prevent the use of damageddatabases. The bacup and restore processes are 0uite comple&" although for the most part

hidden away from us. The most important thing that $ can leave you with is this: do not

arbitrarily delete your transaction logs or checpoint log#doing so may really" really screw upyour weeend. et (&change and the bacup process handle purging these files#its >ust better

that way.

") In *hich Ale mails are store! in outloo6 express an! 4etscapena:iator

.d" files in +hich /utlook 6"press stores folders and identifies e-Mails stored inthem.  A .d" file is the proprietary dataase format in +hich /utlook 6"press storesthe emails. f /utlook 6"press crashes and you cannot find a given d" file orrecover given message from the d" file.

"/) Why ate*ay is use!.

"5) What is the !i0erence bet*een 4 %omain an! W2G %omain

"8) What is $cti:e %irectory an! %irectory ,E#;ICE I4 4"9) What are core component o exchane . an! 2<<<D Whatare connectors<)What protocol are use! in exchane1) Why the concept o client an! ser:er is intro!uce!2) What is the use o maintainin static or manual IP3) What is the main !i0erence bet*een exchane . an!exchane 2<<< ser:er") I a create a ne* user in W2G its comes in *hich roup

)Can *e !eAne ban!*i!th or the synchroniHation on !omain/)%i0erence bet*een WI42G ser:er an! a!:ance ser:er an! WI42<<35)o* to create #oamin proAle

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8)o* to ta6e the ser:er reistry bac6up. What is system state(bac6up)9) What is !i0erence bet*een WI49982GP/<) What is the main unction o router (ype)