Basic of Network

7/30/2019 Basic of Network

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INTRODUCING OF COMPUTER NETWORK

NETWORK

A network is a connection between computer, terminals and networking

device and other components which maintain or allows the transmission of data

between one system to another system.

OR

A network is define as when two or more computer, components terminals

are connected to each other for the purpose of sharing of files.

OR

When two or more computers are able to send and receive any data through

the transmission media (wired or wireless) then it is said to be network.

OR

When communication occurred between two or more computer by means of

environment is said to network.

SOURCE COMPUTER

The computer which is able to send any information or data is called source

computer.

The computer where data is generated from is said to be source computer.

DESTINATION COMPUTER

The computer which is able to receive any information is called destination

computer. Where the data is received is called destination computer.


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NODE:-

The computer which is connected for the purpose of communication is

called NODE.

All the computers which are attached in to the network and help to make

proper communication are term as NODE

SENDER:-

The computer which can send data is sender.

RECEIVER:-

The computer which can receive data is receiver.

FIGURE

Sender Receiver

NETWORKING


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Networking is the ability to share information efficiently for the purpose of sharing

or transferring any information.

OR

Networking is the process by which network can be established to make them

(computer) as a node.

NETWORKING ARCHITECTURE

1. Peer to peer based networking2. Client server based networking

PEER TO PEER BASED NETWORKING

In peer to peer based type of architecture all the computer is attached in simplemanner. All of them are said to be as a NODE

We can attach max.15 devices.

Advantage:-

1. No use of centralized administrator.2. Every computer on peer to peer network function both as server& a client.3. It is inexpensive.4. It can be easily established

Disadvantage:-


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1. User performs as administrator for their own computer.2. No security.3. Additional load of computer for resources sharing.

CLIENT SERVEER BASED NETWORKING

In this type of computer networking architecture all the computers are controlled

by the single computer (server) which is also called centralized administrator.

It consists of many clients and one or more server to provide better security.

Advantage:-

1. Central file stored which allows all users to work from the single location.2. Easy to take back up of critical data.

Disadvantage:-

1. It is expensive to implement because more hardware and software arerequired.

2. Network administrator is required.


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CLIENT COMPUTER:-

The computer which is used to access resources in the network is called

client computer.

SERVER COMPUTER:-

Computer that provide shared resources such as storage and printers and

network server such as e-mail and internet access.

TYPES OF NETWORKING

1. LAN (Local area network)2. WAN (Wide area network)3. MAN (Metropolitan area network )4. PAN (Personal area network)5. SAN (storage area network)6. VPN (virtual private network)

LAN:-

When network is established in a limited area for the purpose of

communication occurred locally, them it is said to LAN.

Generally LAN is established is small offices, Originations etc.

WAN

When communication occurs from one single location to another location

either it belong from the same networks, then it is said to WAN.

Group of LAN is called a WAN which communicates globally.

MAN

When communication occurs among different cities or specific location,

then it is said to MAN.


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PAN

In this type of network communication are established for the purpose of

involving different location.

MODE OF COMMUNICATION

Mode of communication defines the way of communication which is applied

when any communication occurs between the devices. It is the pattern which

resembles that which type of communication occurs.

Basically they are three types;

1. Simplex mode2. Half duplex mode3. Full duplex mode

SIMPLEX MODE:-

In this mode of communication there are only one device is in active state,

means is that only one way communication established. Communication is occurs

due to the broad casting. Example: - Television, Radio etc.

HALF DUPLEX MODE:-

In this communication any device can communicate to another device but at

the time. It means when first device communicate then another device can not

communicate, it is in dumb position. Example: - Walky-talky.

FULL DUPLEX MODE:-

In full duplex mode communication occurs in both ways that all the devices

can communicate to each other at the same time. Example: - Internet, telephone

etc.

TOPOLOGY


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It is define the layout or fashion that in which manner computer are

connected. Topology represents the standard of network and also provides the

information about the following things.

Limitation of networks

Device which are used

Path of communication

Transmission of media

How to troubleshoot

OR

A network topology is the basic design of a computer network. It is very

much like a map of a road. It details how key network components such as nodes

and links are interconnected.

TYPE OF TOPOLOGY

1. Bus topology2. Star topology3. Ring topology4. Mesh topology5. Hybrid topology

BUS TOPOLOGY

In bus topology all the computer are attached with the single backbone. In

this topology computer are connected in peer to peer manner, backbone uses

coaxial cable.

Bus topology is terminated in both sides. Computer is attached to the

backbone with the UTP cable.


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Advantages:-

1. It is the cheapest topology because it does not use any additional device.2. All the workgroup computer are connected in a simple manner, it mean

layout is simple.

3. The entire computer communicates easily without anyinterference/restrictions.

4. Easy to implement new node.5. Good for smaller networks not requiring higher speeds.Disadvantages:-

1. It is not secure connection.2. If backbone cable break then communication is not possible.3. If destination is not available, data is loss.4. Limited in size and speed.

Star Topology:-

In this topology all the computers are attached with central located device

called HUB. HUB makes communication possible because it has many ports to

attached computer. HUB can transmit data from one port to another port directly.


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In a star topology, each network device has a home run of cabling back to a

network hub, giving each device a separate connection to the network. So, there

can be multiple connections in parallel.

This topology generally used UTP or STP cable. It is cheap reliable

topology.

Advantages:-

1. If one workgroup computer is failed another workgroup computer is notaffected.

2. Easy to implement new workgroup computer.3. Communication is quite secure due to the use of HUB.4. More suited for larger networks.

Disadvantages:-

1. It is an expensive topology in comparison to bus topology due to the use ofHUB.

2. If central located device failed then communication become not possible.3. It uses the greatest table length.4. Installation costs are high because each node needs to be connected to the

central switch.


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Ring Topology:-

In ring topology all computer are connected in the form of ring. Ring

topology uses a special device MAU (multi station access unit) logically. MAU

makes communication possible in the form of ring. Ring topology also uses UTP& STP cable.

In a ring topology, the network signal is passed through each network card

of each device and passed on to the next device. Each device processes and

retransmits the signal, so it is capable of supporting many devices in a somewhat

slow but very orderly fashion. There is a very nice feature that everybody gets a

chance to send a packet and it is guaranteed that every node gets to send a packet

in a finite amount of time.

Advantages

1. It uses token ring mechanism.2. Reliable and offers best speed.3. No collision.4. Handle large value of traffic.

Disadvantages:-

1. More cabling is require in comparison BUS topology.2. One fault device affects the entire network.3. Not easy to implement new node.4. Error detection and network administration becomes difficult.


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MESH topology:-

In mesh topology all the computer are connected with each computer end to

end. So for that connection become much more reliable and data travels at very

higher speed. It is special used in WAN link king through router (device).

TYPE OF MESH TOPOLOGY:-

1. FULL MESH: - In full mesh topology all devices are connected with eachand every end for exchanging/transferring of data at higher band width

(speed).

2. PARTIAL MESH: - In partial mesh topology some devices are connectedto only those devices with which they exchange most of data.


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Advantages:-

1. Improve fault tolerance.2. Failure of one link dose not effect on entire network.3. Centralize management is not required.4. Data transmit at very higher bandwidth due to the multiple path ways.

Disadvantages:-

1. Difficult to implement, manage add new node.2. Each link attached with one device to another device, so requires individual

NIC.

3. It is much expensive.

Hybrid topology

Hybrid topology is the combination of two or more different physical

topology commonly star, bus, and ring. It is special topology which is generally


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used in corporate world. It is used to connected different topology in a single

topology. It is used in both LAN &WAN.

Advantages:-

Used for creating larger network handle large volume of traffic fault

detection is easy.

Disadvantages:-

Installation, configuration is difficult more expensive than other topology

because more cabling is required.


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PATH OF COMMUNICATION:-

It define the path (medium) by which the communication is established; there are

two type of path communication.

1. BASEBAND: - In base band type of communication computer can carryone signal at a time and all of the system takes turn to using. To make a

base band communication the data transmitted by each system is spitted

in to separate path called packet. It mean that computer transmit each

packet at a time.

2. BROADBAND: - Broadband is the opposite of base band because it cancarry multiple channels at the same time. It has higher band width and

most effective.


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IP ADDRESS:-

An Internet Protocol (IP) address is a numerical label that is assigned to

devices participating in a computer network utilizing the Internet Protocol for

communication between its nodes. An IP address serves two principal functions in

networking: host identification and location addressing.

The role of the IP address has also been characterized as follows: "A name

indicates what we seek. An address indicates where it is. A route indicates how to

get there.

MAC address:-

In computer networking a Media Access Control address (MAC address) is a

unique identifier assigned to most network adapters or network interface cards

(NICs) by the manufacturer for identification, and used in the Media Access

Control protocol sub layer. If assigned by the manufacturer, a MAC address

usually encodes the manufacturer's registered identification number. It may also be

known as an Ethernet Hardware Address (EHA), hardware address, adapter

address, or physical address.

TRANSMISSION MEDIA:-

The medium (cable, devices etc) through which data can be transmitted from

one point to another is called transmission media. Commonly they are two types.

1. Cables2. Networking device

CABLE:-

Cable is the physical transmission medium which carries data in form of

signal. It has the central conductor of wire surrounded by the plastic jacket.


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Cable are divided into three types according to their speed, cost, need etc.

1. Twisted pair cable2. Co-axial cable3.

Fiber optic cable

1. TWISTED PAIR CABLE:-A twisted pair wire consist of two bunches of thin copper wire and enclosed

separately in a plastic insulator with conductor. One the wire is used to carry the

signal to the receiver and the other is used as ground reference. The connectors

used for this cables are called RJ45 (registered jack).

It is more flexible and easy to bend, cheaper than other cable and easy to

install. They are of two types.

Unshielded twisted pair (UTP)

Shielded twisted pair (STP)

Unshielded twisted pair (UTP)

It content 8 separate copper conductor and they are arranged in 4 pair. The 4

pairs are then encased in a single sheath.


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Category of UTP Cable:-

CAT-1 traditional telephone line carries voice but not data

CAT-2 for data transmission up to 4Mbps



CAT -5 for data transmission up to 100Mbps

CAT-5(e) for data transmission up to 100to1000Mbps

CAT-6 for data transmission up to 1Gbps

Advantages:-

1. In expensive media.2. Easy to install.3. Easy to bend.4. Support up to 1Gbps.

Disadvantages:-

1. Not suitable for long distance.2. Signal can travel only 100 meter.3. Easy gets affected by EMI (electro-magnetic interference).

UTP Cable description:-

Max. Cable length..100 meter.

Band width.100 Mbps.

Connector .RJ 45

Bend radius 360./ fit.

Resistance.. 100 Ohms.

Signal transmission mode.Base band.


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STP Cable:-

It is similar in construction UTP but it has additional foil (layer) or mesh

shielding around each pair. The additional shielding in STP cable makes it

preferable to UTP in installation where EMI is problem. STP is most expensive

than UTP, resistance of this cable is 150 ohm.


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2. COAXIAL CABLEIt consists of a central copper wire surrounded by a PVC insulation

over which a sleeve is again shielded by an outer shield of thick PVC

(plastic) material. The signal is transmitted by the inner copper wire. Co-

axial cable offer much higher band width than twisted pair cable could carry

digital up to 600 Mbps.


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Advantages:-

Shielded allows signal to travel 500 meter.Unrepeated.Relative inexpensive.Medium difficult to install.

Disadvantages:-

Limited to 10 Mbps.Relative unreliable.Only usable in BUS topologyNot the easy to install.Not the least expensive medium.

Type of co-axial cable:-

Co-axial cable is found in to types.

1. Thin net (RG 8):- It is about 0.25 inches in diameter making it flexible. Itcan carry a signal about 185 meters. It uses N connectors.

This network runs at 10 Mbps and uses base band transmission. So for that it

is also called 10 Base 2. The 2 implies 200 meters and 10 imply its speed.We can connect 30 hosts per segment. Its minimum distance between the

hosts is 0.5 meter.


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2. Thick net (RG-58):- It is about 0.38 inches in diameter making it a better

conductor. It can carry a signal of about 500 meters. It uses BNC connector.

Feature of 10 base 5 (thick net):-

1. Base band communication.2. 10Mbps transfer rate.3. Max. Distance of 500 maters/network segment.4. 100host per segment.5. 2.5meters min. distance between hosts.

Description of Cables

Name Description Type Segment Speed

10 Base T Common UTP 5 to 100 m 10Mbps

10 Base 2 thin net co-axial 185 m 10Mbps

10 Base 5 thick net co-axial 500 m 10Mbps

100 Base T Common UTP 5 to 100 m 100Mbps


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3. Fiber optic cable

A fiber optic cable is made of glass or plastic and transmits signals in the

form light because light travels much faster than electricity, physically. A fiberoptic cable consists of three concentric layers, the inner core, a cladding around it

and the outer protective coating. It provides a reliable, secure and very high band

width transmission media.

Type of fiber optic cable:-

1. Single mode fiber optic cable: - it has core diameter of 8.3 micron and

the thickness of the core and cladding together is 125 micron. It referred as 8.3/125

single mode fiber optic. It uses a single wave length laser as a light source and

carry signal for extremely long distance.


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2. Multi mode fiber optic cable: - it is rated as 62.5/125 Multi mode. Ituses a LED as a light source and carries multiple wave length. Both uses subscriber

connector and straight tip connectors.


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CABLE VARIATION

Designation Cable Type Topology SpeedMaximum

Segment Length

10Base5 RG-8 coaxial Bus 10 Mbps 500 meters

10Base2 RG-58 coaxial Bus 10 Mbps 185 meters

10Base-T Category 3 UTP Star 10 Mbps 100 meters

Fiber Optic Inter-RepeaterLink (FOIRL)

62.5/125 multimode fiberoptic

Star 10 Mbps 1000 meters

10Base-FL62.5/125 multimode fiber

opticStar 10 Mbps 2000 meters

10Base-FB62.5/125 multimode fiberoptic

Star 10 Mbps 2000 meters

10Base-FP62.5/125 multimode fiber

opticStar 10 Mbps 500 meters

100Base-TX Category 5 UTP Star100Mbps

100 meters

100Base-T4 Category 3 UTP Star100

Mbps100 meters

100Base-FX62.5/125 multimode fiberoptic

Star100Mbps

412 meters

1000Base-LX9/125 single mode fiber

opticStar

1000

Mbps5000 meters

1000Base-LX50/125 or 62.5/125multimode fiber optic

Star1000Mbps

550 meters

1000Base-SX50/125 multimode fiber

optic (400 MHz)Star

1000

Mbps500 meters

1000Base-SX50/125 multimode fiber

optic (500 MHz)Star

1000

Mbps550 meters

1000Base-SX62.5/125 multimode fiberoptic (160 MHz)

Star1000Mbps

220 meters

1000Base-SX62.5/125 multimode fiber

optic (200 MHz)Star

1000

Mbps275 meters

1000Base-LH9/125 single mode fiberoptic

Star1000Mbps

10 km

1000Base-ZX9/125 single mode fiber

opticStar

1000

Mbps100 km

1000Base-CX150-ohm shielded coppercable

Star1000Mbps

25 meters

1000Base-T Category 5 (or 5E) UTP Star1000

Mbps100 meters


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Cable Problems

Attenuation: -Attenuation is signal deterioration, and noise which is signal

interference can cause problems in networks because the data send may beinterpreted incorrectly or not recognized at all after it has been received.

Noise: - Noise is any electric energy on the transmission cable that makes it

difficult for a receiver to interpret the data sent from the transmitter.

Cross talk: - Cross talk involves the transmission of signal from wire to a nearby

wire, when voltage change on a wire electromagnetic energy is generated. This

energy radiates outward from the wire like a radio signal from a transmitter

adjacent wire in the cable as like antennas and receives the transmitted energywhich interferes with data on that wire.

NETWORKING DEVICES

The device which is used to connect network with cable by which

connection is established and communication become much easier, reliable and

fast is called networking devices. It can be used to extend networks.

The main device which is used in networking is:-

1. HUB2. Repeater3. Bridge4. Switch5. Router

HUB

A HUB or concentrator is a device used to connect all of computer on a star

or ring network. Ethernet HUB is also called a multiport Repeater.

When data enter the Hub through any of its ports, the hub amplifies the

signal and transmits it out through all of the other ports, this enable a star network

to share a single medium even though each computer has its own separate cable.

The HUB relies every packet transmitted by any computer on the network to all of

the other computer while amplifies signal.


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Repeater or HUB work at OSI physical layer to regenerate the network

signal and resend them to other segment. It is physical layer device.

Types of HUB:-Passive HUB: - Passive hub is used to receive data from one port of

the hub and send it out to the other ports. A passive Hub has no power source or

electric component, there is no signal processing and there is no regenerating of the

signal to ensure that it is readable to the destination.

A passive hub simply attached to the ports internally and enables

communication to flow through the network.

Active HUB: - An active hub provides the same functionality as a

passive hub with an additional feature. Active hub rebuilds the data before sendingit to all of the destination port of the hub. Due to this we can increase the length of

network because although the signal weakens with distance. An active hub has apower source and built in repeater to boost the signal.

Hybrid hub:- Hybrid hub is a hub that can use many different types

of cable in additional to UTP cabling. A hybrid hub usually is cabled using thin net


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or thick net along with popular cable type such as twisted pair cabling because it

has many ports.

REPEATER

Repeater is also physical layer device which is used to boost (regenerate) the

signal. The signal are weakens which are coming from long distance so repeater

can be use to solve this problems. Repeater can connect one segment to other

segment. It work with amplified the signal.

Network interface card (NIC)

This device/card install on the system that is responsible for sending and

receiving data on to the network. It is also responsible for preparing the data from

the system to be transparent on the wire by converting the outbound data to electric

signal. This card should be install in expansion slot on the motherboard. Today in

modern computer has build-in LAN card in form of chip it is also called LAN

adapter card or Ethernet card.


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A NIC makes networking possible because it carries a unique code called

MAC address is 48 bit in length and express in 12 hexadecimal digits. MAC

address are some time referred to as burned in address (BIA) because they are

burned in to ROM and are copied in to RAM when the NIC initialized. It is a data

link layer (layer 2) device.

BRIDGE

Bridge is a data link layer device (layer to device). Bridge convert network

transmission data formats as well as perform basic data transmission management.Bridge as name implies, provide connection between LANs, not only do connect

LANs but they also perform a check on the data to determine whether it should

cross the bridge or not, this makes each part to the network more efficient.

Bridge can analyze incoming data packet to determine if the bridge is able to

send the given packet to another segment of the network.


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Bridge learn MAC address of the system by which it creates a table of

source MAC address and destination address called bridging table. Bridging

broadcast their massage only to different segment. It can never broadcast their

massages to its own segment from where source data is generated. This mechanismis possible by the entry of MAC address in bridge table. It reuses network traffic.

Bridge has only two ports either it connect the segment or it break the

segment.

Bridge use two method to resolve the network segment that MAC address

belong to;

Transparent bridge: - This method uses a forwarding data base to send frame

across network segment. The forwarding data base is initially empty and entries in

the database are built as the bridge receives frames. It an address entry is not found

in the forwarding database, the frame rebroadcast to all port of the bridgeforwarding the frame to all segment except the source address.

Source route bridging:- With source route bridging two frame type are used in

order to find the route to the destination network segment single route (SR) frame

makes up most of the network traffic and have set destinations while all-route (AR)

frame are used to find routes.

SWITCH:-

A network switch is a computer networking device that connects network

segment. The term commonly refers to a network bridge that processes and routesdata at data link layer (layer2) of the OSI model. Switches that additionally process

data at the network layer (layer 3 and above) are often referred to as a layer 3

switches or multilayer switches.

The term network switch does not generally encompass unintelligent or

passive network device such as HUB & repeaters.

Switches resemble bridges and can be considered as multiple bridges by

having multiport can better use limited band width and prove more cost effective

than bridge. Switch can transmit its frame to the next port only.


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It is possible because switch also maintain switching table called CAM

(common addressable memory) of both source and destination MAC address. It is

widely used in LAN. It come in various speed, 10 Mbps, 100 Mbps &1 Gbps.

There are four forwarding method of switches.

STORE &FORWARD:- The switch buffer and typically perform a checksum 0n

each frame before forwarding them.

CUT THROUGH:- The switch read only up to t

he frames hardware address before starting to forward it. There is no error

checking with the method.

FRAGMENT FREE:-A method that attempt to retain the benefit to both store &

forward and cut throw fragment free check the first 64 bytes of the framewhere addressing information is stored.

ADAPTING SWITCHING:- A method of automatically switching between theother three mode.

SWITCH CONFIGURATION:-

Unmanaged switch:- These switch have no configuration interface or

option, they are plug and play. They are typically the least expansive switchesfound in home SOHO or small business they can be desktop or rack mounted.

Managed switch:- These switches have one or more method to modify the

operation of the switch. Common management method include; a serial console orcommand line interface accessed via tenant or secure shell an embedded simple

network management station or a web interface for management from a web

browser.

Sub classes of managed switch are:-


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Smart (or intelligent) switches:- These are managed switch with a limited

set of managed feature.

Enterprise managed (or fully managed) switch:- These have a full set of

management features including command line interface SNMP agent and web

interface. They may have additional feature to manipulate configuration such asthe ability to display, modify, back up and restore configurations.

Advantages of switch: -

Switches divide a network into several isolated channels (or collision domains).

Reduce the possibility of collision Collision only occurs when two devices try to get access to one

channel.

Can be solved by buffering one of them for later occurs.Each channel has its own network capacity

Suitable for real time applications e.g. video configuration.Since isolated, hence secure

Data will only go to the destination but not other.

NETWORK ROUTER:-

Network Router is a layer 3 device (network layer). A network connects two

dissimilar network together forming an internetwork when computer on a LANwants to transmit data to a computer on other LAN. The system sends its packets

to a router on the local network and the router forward them to the destination

network. A router will have multiple networks interfaces with each network

interface connecting to a network or a WAN environment. Router typically is used

to connect LAN to a WAN or WAN to a WAN.

Router learns logical address (IP address) for routing. Router has the

following features,

Router work on IP address. Router select best and shortest path. Router perform packet filtering, it connect two different networks

(LAN).

Typically used in WAN. Keep the information of connected router.


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HOW ROUTER WORK

A router forward a packet based on a destination address in the network

layer protocol header, which specify the packets ultimate destination and not the

hardware address used at the data link layer. A router uses internal table (called

routing table) that contain information about the network around it and this tablehelps to determine where to send each packet if the packet destination for system

one of the network to which the router is connected. The router transmits thepacket directly to the system.

Router has multiple broadcast domains and reduces collision domain. There

are two type of routing Static and Dynamic routing.

STATIC ROUTING:- Static routing is a process of creating routing tableinters manually. This is because of network administrator decide what the router

should do when it receive the packets.

DYNAMIC ROUTING:- In dynamic routing router automatically decidewhat to do with packet by the help of routing table.


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ADVANTAGES AND DISADVANTAGES OF NETWORKING DEVICE:-

HUB:-

Advantage:-

Hub can connect many devices than other devices. Hub can transmit data in greater speed. Communication is quite secure due to hub use.

Disadvantages:-

It is an expensive device. It uses the greatest cable length. If centrally located device failed then communication become not possible.

REPEATER:-

Advantage:-

It boost the lose signal. Repeater can connect one segment to other segment. It is suitable for long distance network.

Disadvantages:-

It only regenerates the signals. It is not only suitable for long distance network.

BRIDGE:-

Advantage:-

Bridge can connect two segments. Bridge can transfer data in greater speed. It reduces the network traffic.

Disadvantages:-


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Bridge can transfer data to one segment to another segment. Bridge can not transfer data in own port. Bridge has only two ports either it connect the segment or it divide the

segment.

SWITCH:-

Advantage:-

It also connects two segments like bridge. It has a multiple port. Switch also transfers data to one port to another.

Disadvantages:-

Switches can not transfer data in own ports. It is widely use in LAN. The term network switch dose not generally encompass unintelligent or

passive network device such as HUB and repeater.

GATEWAY:-

A gateway is responsible for translating information from one format to

another format. In other word gateway is used as internet device to convert the data

and packet of the sender in that format that could be easily identify by the

receivable end. The gateway is used in any layer on the OSI reference model

depending on what information gateway translate.

MODEM:-

A modem is a physical layer device that converts digital data originating

from a computer to analog signal. It convert the digital signal into analog signal &

Analog signal to Digital signal suitable for transmission over a telephone line it


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convert the pulse tone (audio tone) into digital tone. Modem is used to

communicate with the system across the PSTN (public switch telephone network).

FIREWALL:-

Firewall is networking component responsible for protecting the network

from outside introduce. The firewall design to block the particular type of traffic

by alloying shortens information to pass through them. The firewall administrator

chooses which traffic can and can not be passed through the firewall. It is specially

used for security purpose.

Measuring bandwidth:-

Units of bandwidth Abbreviation Equipment

Bits per second Bps fundamental unit of bandwidth

kilobits per second Kbps 1 Kbps=103

bps

Megabits per second Mbps 1Mbps=10 bps

Gigabits per second Gbps 1Gbps=109bps

Terabits per second Tbps 1Tbps=10

12

bps


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PROTOCOL: -

A written specification that defines how product should perform a certain

task typically in network. In other word, a protocol is a set of rules which is used

by computer to communicate with each other a cross a network. It is a standardthat control or enable the correction, communication and data transfer between

computing end point. Protocol may be implementing by H/W, S/W or both.

Properties of protocol:-

Detection of under lying physical connection.

Hand shaking.

Negotiation of various connections corrects tactic.

How to start and a massage.

Processor on formatting a massage.

Error correction.

How to detect unexpected loss of the connection.

Termination of the session or connection.

Protocols:-

NCP- network core protocol.

SAP- Service advertising protocol.

IPX- Internetwork packet exchange.

RIP- Routing information protocol.

ADSP - AppleTalk data stream protocol.

AEP - Apple Talk echo protocol.

AFP - AppleTalk filling protocol.

ASP - AppleTalk session protocol.

ATP - AppleTalk transaction protocol.

DDP - Datagram delivery protocol.

LAP - Link access protocol.NBP - Name-binding protocol.

PAP - Printer access protocol.

RTMP - Routing table maintenance protocol.

ZIP - Zone information protocol.

SLIP - Serial line internet protocol.


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CSLIP- Compressed Serial line internet protocol.

PPP - Point to point protocol.

ARP - Address resolution protocol.

IP - Internet protocol.

RARP - Reverse address resolution protocol.TCP - Transport layer protocol.

ICMP Internet control message protocol.

IGMP- Internet group management protocol.

FTP File transfer protocol.

OSI REFRENCE MODEL:-

OSI was developed in 1984 by the international organization for

standardization (ISO) a global federation of national standard organization

representing approximately 130 countries. OSI (open system inter connection)

define a standard a set of rules that allow the networking component tocommunicate easily

The core of this standard is the OSI reference model, a set of 7 layer that define the

different stages data must go through to travel from one device to another device

over a network.

OSI is a system open for communication with other system. The OSI model

has 7 layers the principles were applied to achieve at the 7 layer as follows,

A layer should be created where a different level of abstraction is needed.Each layer should perform a well defined function.The function of each layer should be chosen with an eye to word defining

internationally standardization protocol.

The layer boundaries should be chosen to minimize the information followacross the interface.


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The number of layer should be large enough that distinct function need notbe through together in the same layer out of necessity, and small enough that

the architecture dose not becomes unwieldy.

Figure:-


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THE PHYSICAL LAYER:-

The main task of the physical layer is to transmit raw bits over a

communication channel. It defines the electrical & physical specification for

device. It also defines the relationship between a device and a physical medium. Itinclude layout of pins cable specifications, HUB, Repeater, Network adaptor and

more.

The major function and service perform by the physical layer are:-

1. Establishment and termination of a connection to a communicationmedium.

2. Modulation or conversion between the representation of digital data in userequipment and the corresponding signal transmitted over communication

channels. These all signal operating over the physical cabling or over a

radio link.

3. It converts the frame into multiple bits and then again converts these bits inthe form of electrical signal to transmit data over a medium (cable).

DATA LINK LAYER:-

The data link layer provides the functional and procedural mean to transfer

data between network and entities and to detect and possible correct errors that

may occur in the physical layer.

The main task of this layer is to take a raw transmission facility and transfer

it into a line that appears free of undetected transmission error to the network layer.

To accomplish this, the sender breaks the input data into multiple data frame

(typically of few 100 or 1000 bytes) transmit the frame sequentially and process

the acknowledgement frame sent back by the receiver.

The issues that the layer has to solve:-

To create and to recognize frame boundaries typically by attached specialbit patterns to the beginning and end of the frame.

To solve the problem caused by damaged, lost or duplicate frame (the datalink layer may offer several different services classes to the network layer,

each with different quality and price).


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To keep a fast transmitter from drawing a slow receiver in data. If the line is bi-directional, the acknowledgement frame complete for the

use of the line with data frame.

Broadcast network have an additional issue in the data linklayer, how to control access to the shared channel. A special sub layer of the data

link layer (medium access sub layer) deals with the problems.

The user of the data link layer may be sure that his data were

delivered without errors to the neighbor node. However, the layer is able to deliver

the data just to the neighbor node.

SUBLAYER OF DATA LINK LAYER:-

The data link layer has two sub layers.

Logical link control sub layer:- the upper most sub layer is logical

link control (LLC). This sub layer multiplexes protocols running atop the data link

layer, and optionally provides flow control, acknowledgment, and error

notification. The LLC provides addressing and control of the data link. It specifies

which mechanism is to be used for addressing stations over the transmission

medium and for controlling the data exchanged between the originator and

recipient machines.

Media access control sub layer: - The sub layer below it is MAC.

There are generally two forms of media access control distributed and centralized

both of these may be compared to communication between people.

The media access control sub layer also determines where one frames of

data ends and the next one starts frames synchronization. There are four means of

frames synchronization time based, character counting byte stuffing and bit

stuffing.

Some time this refers to the sub layer that determine who is allowed to

access the media at any time usually (CSMA/CD) other times it refers to a frames

structure with MAC address inside.

NETWORK LAYER:-


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The network layer is layer 3 of the seven layer OSI model of computer

networking. The network layer is responsible for end to end (source to destination)

packet delivery including routing through intermediate hosts whereas the data link

layer is responsible for node to node (hop to hop) frame delivery on the same link.

The network layer provides the functional and procedural means of

transferring variable length data sequences from a source to a destination host via

one or more networks while maintaining the quality of service and error control

functions.

FUNCTION OF NETWORK LAYER:-

Connection model

It is the main function of the network layer which includes two types ofcommunication.

Connection oriented: - Connection oriented is a data transmission attribute

that describes a facility in which the devices at the end point uses a protocol to

established an end to end connection before any data is sent. Connection oriented

transmission is highly reliable.

Connection less: - Connection less mode transmission is a transmission in

which each packet is pretend with a header containing a destination addresssufficient to permit the independent delivery of the packet without the aid of

additional instructions.

Congestion control:-

A router can be connected to 4-5 networks. If the entire network sends

packet at the same time with maximum rate possible them the router may not be

able to handle all the packets and may drop some/all packet. In this context the

dropping of the packets should be congestion is also a function of the networklayer.

Internetworking:-

Internetworking are multiple network that are connected in such a way that they

act one large network, connecting multiple office or department networks.


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Internetwork is connected by networking hardware such as router, switch and

bridges. Internetworking is a solution born of three networking problems, isolated

LANs, duplication of resources, and the lack of a centralized network management

system.

TRANSPORT LAYER:-

The transport layer is responsible for delivering data to the appropriate

application process on the host computers. This involve statistical multiplying of

data from different application processes; i.e. forming data packets, and adding

source and destination port number in the header of each transport layer data

packet together with the source and destination IP address the port numbers

constitutes a network socket, i.e. an a identification address of the process to

process communication.

A byte stream is delivered while hiding the packet mode communication forthe application process. This involves the connection establishment, dividing at the

data stream into packet called segment numbering and reordering of out of order

data.

TRANSPORT LAYER SERVICE:-


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Connection oriented Same order delivery Order delivery Flow control Congestion avoidance Byte orientation Port (Part of the Transport Layer in the TCP/IP model but of the Session

Layer in the OSI model) Ports are essentially ways to address multiple

entities in the same location. For example, the first line of a postal address

is a kind of port, and distinguishes between different occupants of the same

house. Computer applications will each listen for information on their own

ports, which is why you can use more than one network-based application at

the same time.

SESSION LAYER:-

The Session Layer provides the mechanism for opening, closing and

managing a session between end-user application processes, i.e. a semi-permanent

dialogue. Communication sessions consist of requests and responses that occur

between applications. Session Layer services are commonly used in applicationenvironments that make use of remote procedure calls (RPCs).

In case of a connection loss this protocol may try to recover the connection.

If a connection is not used for a long period, the Session Layer Protocol may close

it and re-open it. It provides for either full duplex or half-duplex operation and

provides synchronization points in the stream of exchanged messages.

Within the service layering semantics of the OSI network architecture, the

session layer respond to service requests from the presentation layer and issuesservice to the transport layer.

SESSION LAYER SERVICE:-

AuthenticationPermissions


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Session restoration (checkpoint & recovery)PRESENTATION LAYER:-

Presentation layer is responsible for the delivery and formatting of the

information to the application layer for further processing or display. It relieves the

application layer of concern regarding syntactical difference in data representation

in within the end user systems.

An example of a presentation service would be the conversion of an EBCD-

coded text file to an ASCII-coded file.

The application layer is the lowest layer at which application programmers

consider data structure and presentation, instead of simply sending data in form of

datagrams or packet between hosts.

E3ncryptionand compression should be presentation layer functions,

although they are frequently provide on other layers.

SUBLAYER:-

The presentation layer is composed of two sub layers;

1. CASE(common application service element)2. SASE(specific application service element)

CASE:-

The CASE sub layer provides services for the application layer and request

service from the presentation layer. It provides support for common application

services such as;

ASCE (association control services element)

ROSE (remote operation service element)

CCR (commitment concurrency and recovery)

RISE (reliable transfer service element)


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SASE:-

The SASE sub layer provides application specific services (protocol) such as;

FTAM (file transfer access and manager)

VT (virtual terminal)

MOTIS (massage oriented text interchange)

APPLICATION LAYER:-

The application layer contains all the protocol and method that fall into the

realm of process to process communication via an internet protocol (IP) network

using the transport layer protocols to establish underlying host to host connection.

The common application layer service provides semantic conversion

between associated application processes.

This layer handles issues like network transparency, resource allocation and

problem partitioning. The application layer is censured with the users view of

network (e.g. formatting electronic mail massages). The presentation layer

provides the application layer with a familiar local representation of data

independent of the format used on the network.

The application layer provides the interface to the communication

environment which is used by the application process. It is responsible for

communicating application process parameters.

The host layer also provide for accurate delivery of data between computers in the

network.

TCP/IP

TCP/IP MODEL:-


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PROTOCOLUSED IN DIFFERENT LYER:-


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1. ETHERNET:-Ethernet is the most popular LAN protocol operating at the data link layer. It

was developed in 1970. Todays Ethernet can run at speed of 10, 100 & 1000Mbps

(1Gbps). Ethernet was first developed by digital equipment corporation, Inteland Xerox, which came to be known as DIX Ethernet. DIX Ethernet was first

published in 1980 &defined a network running at 10 Mbps using RG 8 co-axial

cables in a bus topology. This standard is known as thick net, thin net Ethernet or

10base5 Ethernet.

The DIX Ethernet II is standard, published in 1982, and is called as thin

Ethernet, cheaper net or 10base2 Ethernet.

After further development DIX Ethernet added a specification for an UTP

cable options known as 10baseT Ethernet.

Ethernet standard consist of the following 3 basic component:-

1. Physical layer specification2. Frame formats3. CSMA/CD(carrier sance multiple access with collision detection)

Physical layer specification: - it describe the cable used in a network, it

defines the topologies and also cable segment or length.

Frame format:- Ethernet protocol is used to in capsulate the data it receive

from the network layer protocol in a frame, in presentation for its transmission

across the network.

Frame consist of a header and a footer that are divided into field containing

specific information needed to get each packet to its destination regular, fast and

gigabits Ethernet all used the same frame. The frame format an Ethernet is below.

802.3 MAC Frame


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Preamble

Start-of-

Frame-

Delimiter

MAC

destination

MAC

sourceEthernet/Length

Payload

(Data and

padding)

CRC32Interface

gap

7 octets of10101010

1 octet of10101011

6 octets6octets

2 octets461500octets

4 octets 12 octets

641518 octets

721526 octets

Preamble (7 bytes). This field contains 7 bytes of alternating 0s and 1s,

which the communicating systems use to synchronize their clock signals.

Start Of Frame Delimiter (1 byte). This field contains 6 bits of

alternating 0s and 1s, followed by two consecutive 1s, which is a signal tothe receiver that the transmission of the actual frame is about to begin.

Destination Address (6 bytes). This field contains the 6-byte hexadecimal

address of the network interface adapter on the local network to which the

packet will be transmitted.

Source Address (6 bytes). This field contains the 6-byte hexadecimal

address of the network interface adapter in the system generating the packet.

Ethernet/Length (2 bytes). In the DIX Ethernet frame, this field contains a

code identifying the network layer protocol for which the data in the packet

is intended. In the IEEE 802.3 frame, this field specifies the length of thedata field (excluding the pad).

Data and Pad (46 to 1500 bytes). This field contains the data received

from the network layer protocol on the transmitting system, which is sent to

the same protocol on the destination system. Ethernet frames (including the

header and footer, except for the Preamble and Start Of Frame Delimiter)

must be at least 64 bytes long; so if the data received from the network layer


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protocol is less than 46 bytes, the system adds padding bytes to bring it up

to its minimum length.

Frame Check Sequence (4 bytes). The frame's footer is a single field that

comes after the network layer protocol data and contains a 4-byte checksum

value for the entire packet. The sending computer computes this value and

places it into the field. The receiving system performs the same computation

and compares it to the field to verify that the packet was transmitted without

error.

CSMA/CD:- carrier sance multiple access with collision detection

(CSMA/CD), in computer networking is a network access method in which;

A carrier sensing scheme is used.

A transmitting data station that detects another signal while transmitting aframe, stops transmitting that frame, transmits a jam signal, and then wait for

a random time interval (known as back off delay and determined using the

truncated binary exponential back off algorithm) before trying to send that

frame again.

CSMA/CD is a modification of pure carrier sense multiple access (CSMA)

collision detection is used to improve CSMA performance by terminating as soon

as a collision is detected and reducing the probability of a second collision on retry.

Method for collision detection are media dependent, but on a electrical bus

such as Ethernet, collision can be detected by comparing transmitted data with

received data if they differ another transmitter is overlying the first transmitters

signal (a collision) and transmission terminates immediately. A jam signal is sent

which will cause all transmitters to back of by random intervals, reducing the

probability of collision when the first retry is attempted CSMA/CD is layer 2

access method not a protocol OSI model.


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2. TOKEN RING:-IBM originally design token ring but was standardized in IEEE 802.5

document. Token ring network were originally designed to run at 4 mbps & 16

mbps.

It uses a special three byte frame called a token ring frame travel completely

around the loop. Token ring network experience no collision link Ethernet. Token

ring network use ring topology, which is implemented logically inside the MAU,

the token ring equivalent a Hub. When a system receives a frame from the MAU, it

reads the destination address from the token ring header to determine it should pass

or not.

Token ring uses UTP & STP cable. Generally UTP Category 5 with standard

RJ-45 is used. MAU device is also used to make token ring networking possible.

Figure


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Start Delimiter (1 byte). This field contains a bit pattern that signals thebeginning of the frame to the receiving system.

Access Control (1 byte). This field contains bits that can be used toprioritize Token Ring transmissions, enabling certain systems to have

priority access to the token frame and the network.

Frame Control (1 byte). This field contains bits that specify whether theframe is a data or a command frame.

Destination Address (6 bytes). This field contains the 6-byte hexadecimaladdress of the network interface adapter on the local network to which the

packet will be transmitted.

Source Address (6 bytes). This field contains the 6-byte hexadecimaladdress of the network interface adapter in the system generating the packet.

Information (up to 4500 bytes). This field contains the data generated bythe network layer protocol, including a standard LLC header, as defined in

IEEE 802.2.Frame Check Sequence (4 bytes). This field contains a 4-byte checksum

value for the packet (excluding the Start Delimiter, End Delimiter, and

Frame Status fields) that the receiving system uses to verify that the packet

was transmitted without error.

End Delimiter (1 byte). This field contains a bit pattern that signals the endof the frame, including a bit that specifies if there are further packets in the

sequence yet to be transmitted and a bit that indicates that the packet has

failed the error check.

Frame Status (1 byte). This field contains bits that indicate whether thedestination system has received the frame and copied it into its buffers.

The following major vector IDs indicate some of the most common control

functions performed by these packets:

0010Beacon. Beaconing is a process by which systems on a Token Ringnetwork indicate that they are not receiving data from their nearest active

upstream neighbor, presumably because a network error has occurred.Beaconing enables a network administrator to more easily locate the

malfunctioning computer on the network.

0011Claim Token. This vector ID is used by the active monitor systemto generate a new token frame on the ring.


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0100Ring Purge. This vector ID is used by the active monitor system inthe event of an error to clear the ring of unstrapped data and to return all of

the systems to repeat mode.

TOKEN PASSING:-

Each station receive data through a connection from its nearest upstream

neighbor, and transmit data through a connection to its nearest downstream

neighbor. Data transmitted by a station travel sequentially, bit by bit, through each

station. Each station repeats the data, while checking it for errors. The addressed

destination station (s) copy the information as it passes. When the data returns to

the originating station, it is stripped, or removed from the ring.

A station gains the right to transmit data, or frames, onto the medium when

it detects a token passing on the medium. The token consist of a unique signaling

sequence that circulates on the medium following each frame transfer. Any station,

upon detecting a valid token, my capture the token by modifying it to start of frame

sequence and appending appropriate control and status fields, address field, check

sum and the ending frame sequence. After completion of the frame transfer, the

station transmits anew token allowing other station the opportunity to gain access

to the ring.

3. FDDI(Fiber distributed data interface):-FDDI provide a standard for data transmission in a local area network that

can extend in range up to 200 kilometers (124 miles) although FDDI topology is a

token ring network. It does not use the IEEE 802.5 token ring protocol as its basis;

instead, its protocol is dividing from the IEEE802.5 token bus timed token

protocol. In addition to covering large geographical areas FDDI local area

networks can support thousands of users.

HOW FDDI WORKS:-

The computers are actually cabled together in a ring. To provide fault

tolerance in the event of a cable break, the network is a double ring that consists of

two independent rings, a primary and a secondary, with traffic following in

opposite direction. A computer that is connected to both rings is called a dual

attachment station (DAS) and when one of the ring is broken by a cable fault, the


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computer switch to other ring, providing continued full access to the entire

network. A double ring FDDI network in this condition is called a wrapped ring.

The DAC (dual attachment concentrator) creates a signal logical ring like a

token ring MAU. A computer connected to the DAS is called a SAS (single

attachment station). The DAS server have full advantage of the double rings fault

tolerance, whereas the SAS computer attached to the DAC are connected to the

primary ring only. If DAC fails the DAC can remove it from the ring without

disturbing communication to expend the network further, we can connected

additional DAC to port in existing DACs without limit.

Figure


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CSMA/CA:-

Carrier sense multiple access collision avoidance (CSMA/CA) is a

probabilistic media access control (MAC) protocol in which a node verifies the

absence of other traffic before transmission on a shared transmission medium such

as an electrical bus, or a brand of the electromagnetic spectrum.

Carrier sense describes the fact that a transmitter listens for a carrier wave

before trying to send. That is, it tries to detect the presence of an encoded signal

from another station before attempting to transmit. If a carrier is sensed, the station

waits for the transmission in progress to finish before initiating its own

transmission.

Multiple access describe the fact that multiple station send and receive on

the medium transmission by one node are generally received by all other stationusing the medium.

CSMA/CA is a network control protocol in which;

(a) A carrier sensing scheme is used(b)A data station that intends to transmit sends a jam signal(c) After waiting a sufficient time for all station to receive the jam signal,

the data station transmits a frame and

(d)While transmitting, if the data station detects a jam signal from anotherstation, it stops transmitting for a random time and then tries again.

IEEE 802 STANDARDS:-

IEEE 802 LAN/MAN

IEEE 802.1 Standards for LAN/MAN bridging and management and remote media access control

(MAC) bridging.

IEEE 802.2 Standards for Logical Link Control (LLC) standards for connectivity.


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IEEE 802.3 Ethernet Standards for Carrier Sense Multiple Access with Collision Detection (CSMA/CD).

IEEE 802.4 Standards for token passing bus access.

IEEE 802.5 Standards for token ring access and for communications between LANs and MANs

IEEE 802.6 Standards for information exchange between systems.

IEEE 802.7 Standards for broadband LAN cabling.

IEEE 802.8 Fiber optic connection.

IEEE 802.9 Standards for integrated services, like voice and data.

IEEE 802.10 Standards for LAN/MAN security implementations.

IEEE 802.11

Wireless Networking "Wi-Fi".

IEEE 802.12 Standards for demand priority access method.

IEEE 802.14 Standards for cable television broadband communications.

IEEE

802.15.1Bluetooth

IEEE

802.15.4Wireless Sensor/Control Networks "ZigBee"


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IEEE 802.16 Wireless Networking "WiMAX"

Wireless networking:-

Wireless networking allow user mobility, means is that it allow connection

to LAN without having to be physically connected by cable, wireless uses radio

frequency as a transmission media. The technology to transmit and receive data

over air for which user can access shared resources without looking for a place to

plucked in cable, providing that their terminal are mobile and with in the

designated network area, it uses variation on CSMA/CD & CSMA/CA mechanism.

The IEEE802.11 working group was convent in 1990 for the purpose of

developing the global wireless network with a transmission rate of 6, 12, 18, 24,

36, 48& 54 Mbps operate at the frequency range of 5.275 to 5.875 GHz.

The standard has come to be known as IEEE802.11a. the later IEEE 802.11b

standard provide transmission speed of 5.5 Mbps &11 Mbps on June 2003,new

standard was released that is 802.11g at the data rate of 54 Mbps and recently in

Oct2008, 802.11n was released at the data transmission speed of 74 Mbps.

IPERATING MODES:-

IEEE 802.11 defines the following operating modes:

Infrastructure mode Ad hoc mode

In both operating modes, a Service Set Identifier (SSID), also known as thewireless network name, identifies the wireless network. The SSID is a name

configured on the wireless AP (for infrastructure mode) or an initial wireless client

(for ad hoc mode) that identifies the wireless network. The SSID is periodically

advertised by the wireless AP or the initial wireless client using a special 802.11

MAC management frame known as a beacon frame.


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802.11 Infrastructure Mode:-

In infrastructure mode, there is at least one wireless AP and one wireless

client. The wireless client uses the wireless AP to access the resources of a

traditional wired network. The wired network can be an organization intranet or the

Internet, depending on the placement of the wireless AP. An extended service set

(ESS) is shown in the following figure.

802.11 Infrastructure Mode

802.11 Ad Hoc Mode:-

In ad hoc mode, wireless clients communicate directly with each otherwithout the use of a wireless AP, as shown in the following figure.

802.11 Wireless Clients in Ad Hoc Mode

Ad hoc mode is also called peer-to-peer mode. Wireless clients in ad hocmode form an independent basic service set (IBSS). One of the wireless clients, the

first wireless client in the IBSS, takes over some of the responsibilities of the

wireless AP.


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PROTOCOL & TOPOLOGIES:-

The 802.11-related protocols and technologies are discussed in detail in the

following section:

802.11. The IEEE 802.11 wireless standard defines the specifications for thephysical layer and the media access control (MAC) layer.

802.1X. The IEEE 802.1X standard defines port-based, network accesscontrol used to provide authenticated network access for Ethernet networks.

Extensible Authentication Protocol (EAP) over LAN (EAPOL). EAP is aPoint-to-Point Protocol (PPP)-based authentication mechanism that was

adapted for use on point-to-point local area network (LAN) segments.

Wired Equivalent Privacy (WEP). WEP provides data confidentialityservices by encrypting the data sent between wireless nodes.

Wi-Fi Protected Access (WPA). WPA is an interim standard until the IEEE802.11i standard is ratified. These standards, intended to be a replacement

for the WEP standard, offer more robust methods of data encryption andnetwork authentication.

Wireless Auto Configuration. The Wireless Auto Configuration feature ofWindows XP and Windows Server 2003 dynamically selects the wireless

network to which a connection is attempted, based either on configured

preferences or default settings.

INFRARED (IrDA):-

Infrared radiation is electromagnetic radiation with a wave length between

0.7 & 300 micrometer. It wave length is longer than that of visible light but the

wave length is shorter than that of radiation microwaves infrared connectivity is an


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old wireless technology to connect two electronic devices. It uses a beam of

infrared light to transmit information and so0 requires direct line of sight and

operates only at close range. Infrared communication uses high frequency (infrared

beam) to send data transmission between devices.

IrDA (infrared data association) is a standard for transmitting data using an

infrared port. Transfer speed is roughly the same as traditional parallel port. IrDA

is the industry groups that create the IrDA technical standard.

FEATURE OF INFRARED:-

1. It provides speed up to 16 Mbps.2. It provide vary limited range approximately 3 feet and typically7 uses in PANJ,

it uses less power.

3.

It is a secure mechanism because it travel short range between devices4. Infrared was superseded by Bluetooth which has drainage of operating at longdistance (around 30 feet).

BLUETOOTYH:-

Bluetooth is an open wireless protocol for exchanging data over short

distances from fixed a mobile device, creating PAN. It can connect several device

over coming problem synchronization.

Bluetooth is essentially a networking standard that works at two levels;

It provide agreement at the physically level Bluetooth is radio frequencystandard.

It provides agreement at the protocol level where product have to agree onwhen bit are sent, how the parties in conversation can be sure that the

massage sent.

The older Bluetooth 1.0 standard has a maximum transfer speed of 1megabits/second, while Bluetooth 2.0 can manage up to 3 Mbps. Bluetooth

2.0 is a backward compatible with 1.0 device its frequency is about 2.4 GHz.

It was initially conceive by Ericsson.


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IP ADDRESS:-

SUBNETTING:-

Steps of sub netting:-

1. How many subnets? No of subnet=2n where n is the no. of masked bits (1s).2. How many hosts per subnets? No. of host per network =2

n

-2 where n is theno. of unmasked bits (os).

3. What are the valid subnets? 256-subnet mask= block size.4. What is the network address for each subnet?5. What is the range of each subnet? (Valid host).6. What is the broadcast address of each subnet?.


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SUBNET MASK:-

A subnet mask allows us to identify which part of an IP address is reserved

for the network, and which part is available for host use. If we look at the IP

address alone specially with CIDR (class less inter domain) , we cant tell which

part of address is which. Subnet mask gives all the information to calculate

network & host portion of the address for example:-

IP address:-156.154.126.45

Subnet mask:- 255.255.255.240

Subnet mask are critical to communication on an IP network. Network

devices use the IP address target and defined net mask to determine if the network

the host on is a local subnet, or a remote network.

SU8BNET:-

A subnet is a logical origination of network address ranges used to separate

host and network devices from each other to serve as physical or geographical

separation.

BROAD CAST ADDRESS:-

A b/a address is an IP address that we can use the target all system on a

specific subnet instead of single hosts. The broad cast address of any IP address

can be calculated by taking the bit compliment of the subnet mask , sometimes

referred to as the reverse mask , and then applying it with a bit wise or calculation

to the IP address in question.

ISDN (integrated service digital network)

ISDN is a set of communication standards for simultaneous digital

transmission of voice, video, data and other network service over the traditional

circuit of PSTN (Public switch telephone network).


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The key feature of ISDN is that it integrated speech and data on the same

lines. There are several kinds of access interfaces to ISDN defined as BRI (basic

rate interface), PRI (primary rate interface) and broadband ISDN.

ISDN is a circuit switch telephone network system which also provides

access to packet switch network, designed to allow digital transmission of voice

and data. ISDN is designed to provide access to voice and data service

simultaneously.

BRI (basic rate interface):- consist of two B Chanel (64 Kbps) and one D

channel for transmitting control information.

PRI (primary rte interface):- consist of 23 B channels and one D channel.

B for barer channel

D for delta channel

PSTN (public switch telephone network)

PSTN is the global collection of interconnect originally designed to support

circuit voice telephone. The PSTN provides the traditional POTS (plane old

telephone service) to residences and many other establishments parts of the PSTN

are also utilized for DSL (digital subscriber loop), VOIP (voice over I P) and other

internet based network technology.

The basic PSTN network link support 64 kbps band width. Traditional dial

up modem utilized nearly 56 kbps of this band width when connected to a phone

line.

DATA ENCAPSULATION:-

The sending and receiving of data from a source device to the destinationdevice is possible with the help of networking protocols by using data

encapsulation. The data is encapsulated with protocol information at each layer of

the OSI reference model. When a host transmits data to another device across a

network, each layer communicates with its neighbor layer on the destination, each

layer uses protocol data units (PDUs) to communicate and exchange information.


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IMAGE:

PDU (PROTOCOL DATA UNIT):-

The PDU contains the control information attached ton the data at each

layer. The information is attached to the header of the data field but can also be inend of the data field or trailer. PDUs are encapsulating by attached them to the data

attached layer of the OSI reference model.

DE-ENCAPSULATION:-

On destination side, the receiving device will synchronize on the digital

signal and extract the 1s and 0s from the digital. At this point the devices build the

frame, run a cyclic redundancy check (CRC) , and then check their output against

the output in the frame check sequence (FCS) field of the data frame, if the

information matches then the packet is pulled from the frame, and the frame isdiscarded. This process is known as de-encapsulation.


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IMAGE:-

HOW TO MAKE A NETWORK CABLE:-

1. Unroll the required length of network cable and add a little extra wire, just incase.

2. Carefully remove the outer jacket of cable.3. Inspect the newly revealed wires for any cuts or scraps that expose the copper

wire inside.

4. Untwist the pair so they will lay flat between your fingers.5. Arrange the wires based on the wiring specification you are following:-

there are two method set by the TIA, 568A and 568B. Which we used will

depend on what is being connected. A straight through cable is used to connect

two different layer devices (hub & a pc). Two like devices normally require a

cross over cable. The difference between the two is that a straight through

cable has both ends wired identically with 568A, while a cross over cable has

one end wire 568A and the other end wired 568B for our5 demonstration in the

following steps. We will use 568B but the instructions can easily be adapted to

568A.

568A:- put the wire in the following order, from left to right.


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White orange Orange White green Blue White blue green White brown Brown568B:- from left to right; white green, green, white orange, blue, white blue,

orange, white brown, brown. We can also use the mnemonic 1-2-3-6/3-6-1-2

to remember which wire is switched.

white green green white orange Blue white blue Orange white brown Brown

6. Press all the wires flat and parallel between our thumb and fore finger.7. Keep the wire flat and in order as you push them into the rj-45 plug with the

flat surface of the plug on top

ROLL OVEER CABLE:-

A rollover cable is used with each pin on one end of cable connected to the

reverse pin on the other end. So the cable on pin 1 on one end of the cable connectsto pins at the other end, etc. rollover cable are used to connect the serial port of a

network switch so that you can configure the network switch. These cables are not

used for network connectivity.


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SWITCHING TECHNIQUES:-

Switching techniques are used for transmitting data across the networks. 3

types of switching techniques are there, circuit switching, message switching,packet switching.

CIRCUIT SWITCHING:-

Circuit switching physical connection between the two computers is

established and then data is transmitted from source to destination computer. When

a computer places a telephone call, the switching equipment within the telephone

system seeks out a physical copper path from senders to receivers telephone. It

sets up end to end connection between computers before any data can be sent.

MASSEGE SWITCHING:-

Massage switching the source computer sends the data to the switching

office first which store the data in its buffer. It then looks for a free link to another

switching office and then sends the data to this office. Process is continued till the

data is delivered to the destination computer. It is also known as store and forward

technique.

PACKET SWITCHING:-

Packet switching there is a tight upper limit on the block size. In massage

switching there was no upper limit. A fixed size of packet is specified. All the

packets are stored in main memory in switching office. In massage switching

packets are stored on disk. This increases the performance as access time is

reduced.


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NETWORK MANAGEMENT:-

Network management is the process of controlling a complex data network

to maximize its efficiency and productivity.

The overall goal of network management is to help with the complexity of a

data network and to ensure that data can go across it with maximum efficiency and

transparency to the users.

The international organization for standardization (ISO) network

management forum divided network management into five functional areas;

Fault managementConfiguration managementSecurity managementPerformance managementAccounting management

FAULT MANAGEMENT:-

It is the process of locating problems or faults, on the data network. It involves the following steps;

Discover the problem Isolate the problem Fix the problem (if possible)

CONFIGURATION MANAGEMENT:-

The configuration of certain network deices controls the behavior of the datanetwork.

Configuration management is the process of finding and setting up(configuring) these critical devices.


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SECURITY MANAGEMENT:-

It is the process of controlling access to information on the data network. Provides a way to monitor access points and records information on a

periodic basic provides audit trails and sounds alarms for security breaches.

PERFORMNCE MANAGEMENT:-

Involves measuring the performance of the network hardware, software andmedia.

Example of measured activities are;

Overall throughput. Percentage utilization. Error rates. Response time.

ACCOUNTING MNAGEMENT:-

Involves tracking individuals utilization and grouping of network resourcesto ensure that users have sufficient resources.

Involves granting or rumoring permission for access to the network.

NETWORK OPERATING SYSTEM:-

A network operating system (NOS) is a peace of software that controls a network

and its message, traffic and queues, control access by multiple user to network

resources such as files and provide for certain administrative function including

security. It is use in both LAN & WAN.

NEEDS OF NOS:-

It provides basic operating system feature such as support for processorprotocol, automatic hardware detection.


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Security feature such as authentication, authorization logon restriction andaccess control.

Provide name & directory services.Provide file, print web services etc.Highly fault tolerant and highly capable.

NOVELL UNIX WINDOWS LINUX

Netware HP-UX NT Red hat

Internet were sun Solaris 2000 server Caldera

BSD Net server Sues

SCO server 2003 Devins

AIX Server 2008 Slack ware

NOS CONSIDERATIONS:-

security Encryption user authentication

robustness balanced workload redundancy

performance consistency overstrain

scalability ready for growth

management system administration

WINDOW OS:-

window NT work station corporate users

Server department server

window 2000 Professional corporate uses or small

Server intent or remote access server

advantage server department serverNet enterprise server

enterprise server

enterprise internet server


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NETWORK MANAGEMENT PROTOCOL:-

A simple protocol defines common data formats and parameters and allowsfor easy retrieval of information.

A complex protocol adds some change capability and security.An advanced protocol remotely executes network management task is

independents of the network layer.

The most common protocols are;

SNMP(simple network management protocol) SNMP v2(SNMP version 2) CMIS/CMIP(common management information services/common

management information protocol)

SNMP is beyond the simple protocol with adequate monitoring capabilities and

some change capabilities.

SNMP v2 greatly enhances the SNMP feature set.

CMIP/CMIS approaches the advantage tool but implementation issues have limited

its use.

SNMP:-

At the end of the 80s a solution was chosen called the internet standard network

management framework.

This was a set of three documents defining.

A set of rules for describing management information. An initial set of managed objects. A protocol used to exchange management information.


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DNS (domain name system):-

The domain name system (DNS) is a hierarchical naming system for

computer, services or any resource connected to the internet or a private network.

It associates various information with domain names assigned to each of the

participants. Most importantly, it translated domain names meaningful to humans

into the numerical (binary) identifiers associated with networking equipment for

the purpose of locating and addressing these devices worldwide.

No often used analogy to explain the domain name system is that it serves as

the phone book for the internet by translating human friendly computer

hostnames into IP address for example; www.example.com translates to

208.77.188.166.

NET BIOS:-

Network basic input output system is a program that allows applications on

different computer to communicate with in a local area network. It was created by

IBM for its early PC network, was adapted by Microsoft. Net BIOS is use in

Ethernet and token ring networks and included as part of (net BEUI), in resent

Microsoft windows operating system.

Net BIOS provides the session and transport services described in the OSImodel. It does not provide a standard frame or data format for transmission. A

standard frame format is provided by net BEUI.

NETWORK TROUBLESHOOTING COMMAND:-

Computer network can have different kinds of problems such as it can be infected

with virus, attached by hackers, accessed by unauthorized users and may face

connectivity failure issues due to the faulty network devices or configuration.

Using following trouble shooting command can help him diagnosing andresolving the issues with our computer network.

PING: - ping is the most important trouble shooting command for checking the

connectivity with the other computer.

Ping


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IPCONFIG: - it shows the IP address of the computer and also it shows the DNS,

DHCP, Gateway addresses of the network & subnet mask.

IPCONFIG /ALL: - it shows the details information of whole network parameter

like IP, MAC, Subnet mask, LAN connectivity.

NSLOOKUP: - Nslookup is a TCP/IP based command and it checks domain name

aliases, DNS record, operating system information. This command is specially

used to resolve the errors with the DNS of our network server.

HOST NAME: - host name command shows our computer name.

NETSTAT: - this utility shows the protocol statics and the current established

TCP/IP connection in the computer.

NBTSTAT: - it helps to troubleshoot the NetBIOS name resolution problem.

ARP: - ARP displays and modifies IP to physical address translation table that is

used by ARP protocol.

TRACERT: - it is used to determine the path of the remote system. It also

provides the no. of hopes and the IP address of each hope.

Tracert

TRACEROUTE: - trace route is the network debugging command and it is used

in locating the server that is slowing down the transmission on the internet and it

also shows the route between the two system or two hopes.

Trace route

ROUTE: - route command allows us to make manual entrees in the routing table

Documents

Basic of Network