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What is Needed For Video Conferencing?

y The Most Important Part Is Obviously the Video/Microphone- For the Home Users, This Comes in Several Flavors; The Most Popular Are:

1) Creative Lab's WebCam 2) Intel's PC Cam

&3) Logitech's Quickcams

{for review and pricing of the products, go to ZDNet's Review Section}

y The Second Component is a "Codec"- An Abreviation in this usage meaningCoder/Decoder.

-The codec serves the same purpose as a modem (a modulator/demodulator) inthe sense that it converts the digital signals into analog signals in order to becarried over the phone lines.

-On the other side, the viewer also has a codec which converts the analog signalback to digital, all in real time. {A codec is included in the cameras sold tohome users and businesses}

y The last component is the software. One of the most popular and oldestprograms is CU-SeeMe. This program basically reduces video conferencing to

point-and-click action.

image modified from Univ of Missouri Site

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oAnother program gaining in popularity is Microsoft's Netmeeting. It isincluded in Windows 2000 and includes file transfer, internet chat, andwhiteboarding in its list of options.

image modified from Microsoft's Netmeeting Site

y These components, combined with a monitor/TV allow for video conferencing.As long as the IP addresses of the various users are known, everything shouldrun smoothly.

Why Is It Useful?There are many uses for video conferencing. The most obvious is business. B2B(business to business) video conferencing is quickly rising in popularity, especially ascommunication lines become faster. Also, video conferencing combined withwhiteboard and file sharing allows fast collaboration between workers and customers.

A new use for video conferencing is actually education. One way in which it used isto provide a good education for less. For example, a foreign language class can havea guess visitor from a foreign country without the cost of airfare. Experts in most anyfield can give lectures on their area of expertise using the multipoint/room system of

video conferencing.

Other applications include:

y Telemedicine: This is basically when a doctor helps to diagnosis apatient by video conferencing with the local doctor and patient. This isespecially useful in rural areas, where a specialist in the city can helpwith a patient who is far from the needed specialized care.

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y Telecommunicating: Although not extremely popular as of yet, it is anappealing thought to be able to work without ever going to work. As ofnow, it is more useful for the occasional day when one cannot or doesnot go to work.

y Courtroom: The most useful application of video conferencing in thecourtroom is for "video arraignments". In this case, prisoners (especially

dangerous ones) never have to leave the jailhouse.

y Laboratory Work: Video conferencing can be extremely cost-effectivedue to the high cost of most advanced lab equipment. Also, it can bringtogether, similiar to classroom conferencing, the experts in their field

together for a single experiment.

How Will It Improve?

Obviously, it will get faster. This really is the only improvement needed. Today's

computers are definitely fast enough to handle video, as can be seen by thewidespread video editing packages designed for home users. The only bottleneck isthe connection between the computers or video sources. But even this is improvingdrastically. Not too long ago, 2400 baud was the way to view the internet. Now 56khas taken over, and DSL and Cable are about to eclipse this. Prices seem to besteadily dropping as availability tends to be rising. In roughly two years, either one ofthese connections will be cheap enough and accessible enough that they'll start to bethe a large chunk of the internet connection game. Once this happens, videoconferencing will follow suit.

Different Types of Video Conferencing

The are basically two types of video conferencing. The first is point-to-point.

The second is multipoint.

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y Point-to-Point is the most basic video conferencing and most common. Itinvolves using individuals IP addresses to directly connect the two users.

This is the most common form for home users. It is also used as a form of

video phone.

yMultipoint Conferencing throws in several variations:oThe first is a reflector, multipoint connector unit (MCU) or

"multipoint bridge". This is a device which is needed for three or

more users that serves as the central hub onto which all the users

connect. It can either be a stand-alone device or a computer server.oThe next is the setup of the equipment. Point-to-Point usually uses

two PCs. In mulitipoint, however, the users can use Room Systems

and Roll-About Systems in addition to PCs. A room system is a large conference room which houses

several cameras/microphones and allow large groups of

people to participate at once. A roll-about system is just a cart which houses the camera,

microphone and codec all in one unit. This is good for small

groups of people.yWith all of these systems, there are multiple options. The most common

are document sharing and whiteboarding.y For a comprehensive look at all the different possible setups, check out

the Video Development Initiative's site called "Video Conferencing

Cookbook".

What Are the Drawbacks?

As of now, the largest drawback of video conferencing is that for most people, itsjust not convenient. This is largely due to the fact that most people still connect to theinternet through regular copper phone lines. With download speeds limited to 56kbpsand upload limited to 33.6kbps, it's not surprising that video conferencing hasn'tcaught on to many home users. Most experts would say that the bare minimum forvideo conferencing is dual ISDN lines, running at 128kbps. Even this, though, isstretching it. With speeds greater than this (i.e.xDSL or Cable) video conferencingwill be more of an nuisance than a tool to most home users.

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With this need for speed, video conferencing also carries another problem for mosthome users: price. DSL lines and Cable Lines have an initial charge of $200-$500 formost users, that is if the technology is even available where they live. Then themonthly charge is roughly $50, a leap in price compared to the $20 or even sub-$20most people pay for regular phone line access.

Furthermore, DSL may offer speed but it might not always offer videoconferencing. Some types of video conferencing are not always compatible with

some types of DSL

MSN.

See when your friends are online and send them instant messages!Have group conversations. Be notified when you receive new e-mail to your MSN Hotmail account. Add instant messagingcapabilities to Outlook Express. Invite your friends to a WindowsNetMeeting conference or to play a DirectPlay game. Controlwho can see when you are online and send you messages. Andmore! To read more about MSN Messenger Service, click here.

The Basics

View online status and exchange instant messages: You can seewhen your friends are online and exchange instant messages withup to four of them at the same time. It's like knowing whethersomeone is home before calling them on the phone! And instantmessages are fast--even faster than e-mail! Automatic typingindicator: Conversations are easier to follow because MSNMessenger Service will tell you when one of your friends is in theprocess of typing a response. Customize online status: You havecontrol over your online status and how it appears to others. If youare busy and unable to talk, for example, you can change yourstatus to Busy. You can even choose to appear as if you areoffline. Plus, if you are inactive on your computer for severalminutes, your status will automatically change to Away so thatyour friends know you might not respond quickly. Richcustomization: Not only can you customize your instant messages(font, color, size, etc.), you can designate special sounds

that play when you receive an instant message or a friend comesonline as well as designate that MSN Messenger Service alwaysappears in the foreground so that you always have access to its

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features. Auto-update: Whenever there is an update to MSNMessenger Service, you will be notified and have the opportunityto quickly upgrade to the latest software.

Seamless Communications

Easy access to Hotmail: You can see how many unread Hotmail e-mail messages you have from the new Mail button and are notifiedwhenever you receive a new Hotmail e-mail message. Instantmessaging in Outlook Express: With MSN Messenger Serviceinstalled, the Outlook Express 5 Contacts pane will automaticallyinclude online status information of your friends (Online, Busy,etc.). You can even send friends instant messages from withinOutlook Express. Invite friends to a NetMeeting or to play agame: You can invite friends to participate in a NetMeetingsession or to play a DirectPlay game directly from within MSNMessenger Service.

Privacy and SecurityControl over your information: You have complete control overwho can view your online status and send you instant messages.Plus, at any time you can see a list of who has added you to theircontact list. Password encryption: MSN Messenger Serviceencrypts user passwords so that the code sent can only bedeciphered by MSN Messenger Service.

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Yahoo instant messenger

In the lastest version the features include:Status Icons - See when your friends are idle or busy just by looking

at their icon.New Voice Chat - The latest version of our Voice Chat supportshandsfree conversations and allows you to talk and listen at the sametime!Calendar, Stock, News, Scoreboard, Weather, Bookmarks, Travel(fares), Overview, and Auctions Tabs - See your day at a glance,check on your stocks, see top headlines, check the lastest scores ofyour favorite games, check your mail, and much, much more!Search For Friends - The new version of Yahoo! Messenger has apowerful member directory search that is built into the applicationMinimized Messages - Minimize incoming messages to yourtaskbar.Better Notification Messages - Now Messenger will notify you of thesubject and sender for your new Yahoo! Mail messages, as well asnotifying you when your friends are online. You are able to leavemessages for your buddies that are off-line. When the buddy signsback online he will receive the message that you left for him.Fonts, Colors, and Sounds - Change the default font for all yourinstant messages, or for individual messages. There are many soundsthat you can choose from when your buddies sign on and off-line andeven when you are typing your messages.Improved Theme Support - Now you can change the default colorsfor each of your different themes.

There is a buddy list where you can create different names forthe different kinds of "buddies" that you have. For example you mayhave one group named family, and another co-workers. There is aweb page made by Yahoo just for "creating and editing yourgroups." The directions are very easy and self explanatory.

After you add a group it asks you to add a buddy to this group.You can then send a message to the buddy and he will receive the

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message the next time he signs on to the Yahoo Messenger.

CONNECTING MODERM

Almost everyone outside of a university or business setting is connectingto the internet using a modem. Everybody knows that they are used toconnect to the internet, but do you know how they do it? For instance,computers operate in the digital world, but telephone lines require adifferent method of transmission. The modem is what handles thisconversion. Modem stands for modulator-demodulator. The modemmodulates the signal into a sine wave. This in turn can be broadcast overa telephone line. The signal is tranmitted over the line until it reaches theIP hub. At this point, the sine is demodulated into a digital signal oncemore, and the connection with the internet is complete. Modems can dothis at a variety of speeds depending on the technology and availabilityof access lines. The industry standard now is 56K which stands for56,000 bits per second (bps), the maximum transmission speed of themodem. This can also be read as 56K Baud, which stands for the amount

of state changes undergone by the transfer of information, i.e. the 0's and1's in a digital signal and the manipulations in a sine wave. Due to speedlost in transmission and the quality of hardware and communicationservices, the maximum attainable speed is usually around 53K.

Simple connectionHow fast modems transfer information is based on how they

convert it. Modems must change the sine wave in order to emulate thedigital signal. They do this based with the commonly known Amplitude

modulation (AM), Frequency modulation (FM) and the less known

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Phase modulation (PM). As their names suggest, the sine waves'amplitudes, frequencies and phases are manipulated to emulate the

digital signal.Amplitude Modulation

Frequency Modulation

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Phase Modulation

You can see the relationships from the graphs above. For higher speed

modems, such as anything above 9,600 bps, a combination method is required in

order to transmit that much information. High speed modems use Quadrature

Amplitude Modulation (QAM) which simultaneously changes both the phase and

amplitude of the signal. Here a 32 point "constellation" represents one of 32

signals, each encoded with a 5 bit signal. This means that a 2,400 Baud signal cantransmit at 12,000 bps (2400 signals at 5 bits a signal).

top

How does ADSL work?Asymmetric Digital Subscriber Line (ADSL) uses a more complex

monitoring system to increase the speed of connections. The slowest part of the

transmission over phone lines was the connection between the phone and the

local substation for demodulating the signal. The telephone lines between your

house and the phone company are comprised of twisted copper wire which have

maximum bandwidth under 3 miles of 1.1 MHz. Along the wire the bandwidth

varies between 24 kHz and 1.1 MHz. This spectrum is divided into 249, 4 kHz

channels. A signal is assigned to one of these channels based on the bit rate and

quality of the signal. This way, many more signals can fit on at higher speeds.

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Division of Signals in ADSL

How does Ethernet work?The ethernet, the wonderful thing that allows for supremely fast MP3

downloads and the ability to be on the computer without tying up your phone

line. But do you know why you can do that? The ethernet is the most commonly

used Local Area Network (LAN). A network is a group of computers, usually

called a "user group", that share information. These computers all connect to the

internet and to each other at a small substation. At this substation, there is an

extremely high speed transmission line with a large capacity for users. This line

is constantly connected to the internet, which accounts for the extremely fast

internet connection and reason you don't have to dial a number to get on. These

lines are commonly called T-base lines. T-1, T-2, T-3 are the commonly knownones. These are all variants of the same concept, with T-3 being the fastest. At the

University of Delaware, we are currently operating on a 10BaseT ethernet

network with multiple T-1 lines as the main out-going lines. All the T-1 lines

added up give the University the equivalent of a T-3 line, which runs at

45Mbps(45 Megabit), approximately 28 T-1 lines. The 10BaseT that the

infomation is being transferred at 10Mbps over a twisted wire line. A "hop" is

when the signal has to run through other systems to get to the internet.

Unfortunately, the signal goes through three "hops" before going to the internet,

so it may not always connect at 10Mbps. This is because ethernet runs at 10Mbps

over shared network lines, but not necessarily through T-base lines. In order tooperate on the ethernet, each PC must have a working ethernet network card.

This card must be configured to read the desired network. Ethernet works on

CSMACD protocol. This stands for Carrier Sense, Multiple Access, Collision

Detect. The "carrier sense" means that, before transmitting, the wire checks to

make sure no one else is transmitting. The "multiple access" means that

everyone is connected to one outgoing unit, i.e. the T-base line. When two

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stations start transmitting at the same time, they collide nanoseconds later. This

is where the "collision detect" comes in. When a collision occurs, both signals

"back-off" and then wait a pre-programmed amount of time before processing

again. A repeater is used when one common type of wire is not convenient to wire

an entire building or campus. It's a small transfer box which takes in the signal

from one wire and then spits it back out bit-for-bit to the other wire. top

Impact

The impact of the modem is unparalleled in recent events. The ability to

surf the internet has led to an information explosion the world has not seen. The

ability to access trillions of bytes with a double click has led to a revolution, an

information revolution. Knowledge is no longer found only in books contained

only at the local library, it is found in the home. The improvements in modem

technology are improving at a phenomenal rate. It is possible to access things in

the home never before thought possible.

ADSL is still new, but the promise is substantial. 10Mbps is on par with our

ethernet connection at the University. Once that kind of speed is available in the

home, information transfer will be even quicker. Applications too large to be

handled by a modem will become more commonplace. This means an improved

internet which will benefit everyone.

There is not a student at the University who does not kiss the wires the

network travels on. I had heard stories about how great it was, but I had no idea

until I came here. It has opened up a whole new part of my life. I was not on theinternet a lot when I was in high school simply because it took a good seven

minutes from boot-up to log-in. Now, a day doesn't go by when I am not on it for

something. It has impacted every student at the University of Delaware as well as

hundreds of thousands of students nationwide. As for the private sector, large

scale businesses rely heavily on it for data tranference. Some so much so that

they have 100BaseT networks installed. That's 10 times faster than the

University's current network. Research is almost complete on perfect the gigabit

network becasue the institutional demand is there.

There is a percentage of the population that is not on the internet and whose

lives have not been effected in some way by the information explosion, but they

live in the hills ofMontana and shoot at targets all day, so they won't read this.

92 Million people in the US and Canada over the age of 16 use the internet. An

18% increase from just 9 monthes ago. (survey dated April, 99. courtesy commerce.net) The bottom

line is that without the connection and the improvements on the connection, we

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would be lost in the limbo of ignorance, forever doomed because of the

inconvenience of obtaining knowledge. The internet has helped us in ways we can

not even understand and in a world where everything should have been done

yesterday, the faster the connection, the better.

E-MAIL

History of e-mail In October of 1971 a computer engineer, named Roy Tomlinson, sent

the first e-mail message. Ever since that day, our lives have never beenthe same. Prior to his discovery, messages could only be sent to users

on a single machine. Tomlinson's finding enables us to send messagesto other machines on the Internet.

In the beginning the program called "Eudora" was a commonly used

form of e-mail, since it was usually included in the software packageprovided by the ISPs (Internet Service Providers). As the popular

ISPs, such as Netscape and Microsoft Internet Explorer, began toimprove they usually included stronger e-mail programs and Eudora

was eventually pushed to the side, although it is still used by sometoday.

How does e-mail work?? In order to send an e-mail one must first have an e-mail client. This

client can be a free e-mail service such as Hotmail or Yahoo Mail, theever-popular AOL, or other clients like Microsoft Outlookor Outlook

Express. An e-mail server is necessary for the client to connect to.

The Internet has millions of FTP servers, telnet servers and e-mailservers running on it all the time. These servers listen to different

ports while they wait for people to attach to these ports. The e-mailsystem operates on the basis of two different servers-the SMTP

(Simple Mail Transfer Protocol) Server and the POP3 (Post OfficeProtocol) Server. The SMTP server handles outgoing mail and

listens on port number 25. The POP3 server handles incoming mailand listens on port number 110. A typical server looks something like

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this:

borrowedfrom:http://www.howstuffworks.com

Whenever an e-mail is sent the SMTP server interacts with the e-mail

client. The POP3 server maintains a collection of text files for each e-mail account. Once an account has been logged into, the POP3 server

opens the text file and allows access to it. Most e-mail clients alsoallow attachments to be added to e-mail messages and to be saved from

received messages.

Advantages and disadvantages of e-mail

A recent study done by the Stanford Institute of Quantitative Study of

Society found that 84% of Internet users said they used e-mail. Thereare an estimated 300 million e-mails being sent per day in the UnitedStates. It has become an all encompassing part of many people's daily

lives. E-mail has become a way for people to obtain jobs, for doctors tocommunicate more effectively with patients, for professors to

maintain better contact with their students, and for long-distancefriends and family members to stay in touch.

With all the advancements that e-mail has made in the past three

decades, there are some disadvantages. The growing speed andaccessibility of this technological device has resulted in a loss of

personal human interaction. There are many who fear that with thespread of e-mail comes the further isolation of humanity. Professor

Norman Nie, of Stanford University, said in a recent article that "E-mail is a way to stay in touch, but you can't share a coffee or a beer

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with somebody on e-mail or give them a hug. The Internet could be the

ultimate isolating technology that further reduces our participation incommunities even more than television did before it."