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always selected at the time of transmission, after taking current network 
conditions into consideration. <BR><BR>The network designers also felt it was 
important to distribute route-selection capabilities throughout the network, so 
that no single site was responsible for the entire network. Let me explain this 
further, lets say like a network was designed " hierarchically " so that 
everything passes through that central routing site, so if anything happens to 
that central routing site well HOUSTON WE GOT A PROBLEM! <BR><BR></FONT></P><PRE><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2>This is how a hierarchically network would look like:
<BR>
<BR><FONT size=1>----------------------------------------------------------------------------<BR></FONT>                            ___<BR>                           |___|
                           / \ / \       Well you can clearly see that the
                          /  /\   \      big box is the central routing site 
                        O O O  O    so if anything happens to the big <BR>                                          box then we got a big problem.

<FONT size=1> </FONT></FONT><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2><FONT size=1>----------------------------------------------------------------------------</FONT></FONT>
</PRE>
<P><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2>So since these guys 
were very smart they built the Internet in "heterarchically," which really means 
instead of having one central routing site, there are a large number of routing 
sites distributed all over the network. The hosts that decide how to route 
transmissions across the Internet are called ROUTERS. The Internet today is 
currently being run by thousands of these hosts called routers. 
<BR><BR></FONT></P><PRE><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2><FONT size=1> </FONT></FONT><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2><FONT size=1>---------------------------------------------------------------------------------</FONT></FONT><BR><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2>
                          O-O     Okay the art sucks but you see the idea
                        / -O- \    there isn't one box there are many hosts<BR>                       O-----O   so if one dies, others can still work
                         \ O /
<FONT size=1> </FONT></FONT><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2><FONT size=1>---------------------------------------------------------------------------------</FONT></FONT><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2> </FONT></PRE>
<P><FONT face="Verdana, Arial, Helvetica, sans-serif" size=2>So now you figured 
out the difference, dynamic heterarchical routing is what makes the Internet 
work so good, and the key idea that binds everything together is packet 
switching. All of the data moved across the Internet is moved in units called 
PACKETS. The traffic on the net is measured by counting the packets transferred 
in a period of time. <BR><BR>If this concept is hard for you to understand let 
me explain. Lets say you are downloading a file from a server in California to 
your box in New York. The software running on the server breaks the huge file 
into packets. Lets say your file was 100k it might be broken down info 6 or 7 
packets, then each packet is stamped with the IP address of its destination, as 
well as the IP address of the originating host. Packets will also be given 
instructions, these instructions describe the size of the original transmission 
and where each specific packet should be positioned when the original 
transmission is put together when it gets to my computer. Now the big deal is 
that each packet is sent out onto the Internet to find its way to the 
destination address. This means that the 6 or 7 packets don't have to travel 
together so they can go from California to other parts of the country then they 
find their way to New York. The packets are first given to a router, which looks 
at their destination address and decides where to send the packets. Now the 
router at that location then does the same thing. So when all the packets come 
to New York, they are then assembled into a single file. Each packet is checked 
first to see if it has arrived intact. If there was an error in a packet then a 
request to resend that packet is sent to the originating host. This form of 
sending files is the best way to work on a net, because it minimizes network 
load and by sending small packets the destination won't have to wait for the 
whole file to be sent if it had errors. Every computer running on the Internet 
uses this form of data transfer. <BR><BR><BR><B><FONT color=#ffffff>Important 
newbie fact <BR></FONT></B><FONT color=#ffffff></FONT><BR><BR>Well if your 
reading this you probably were alive in 1996, well what's the big deal you ask, 
lets put this concept of packet switching into the real world. On August 7, 
1996, 6 million AOL customers were unable to access the Internet because AOL had 
recently loaded new software onto its network routers. This software contained 
incorrect routing information. As a result, AOL couldn't route packets on or off 
its gateway hosts. The 6 million guys waiting soon found out that their aol 
service was interrupted and for 19 hours these guys couldn't surf the net. Now 
since only AOL had this problem, the rest of the world who are smart enough not 
to use aol were checking their email and chatting and visiting sites, thanks to 
the architecture of the net not all of us suffered. <BR><BR><BR><B><FONT 
color=#ffffff><A name=band></A>5: Bandwith and Asynchronous Communication 
<BR></FONT></B><FONT color=#ffffff></FONT><BR><BR>Okay, you're probably saying 
what's this topic Mike? Its nothing to fear, i'll explain in simple English a 
little child can understand. <BR><BR>Online communication takes some time for 
normal people to understand or to just get used to. In the world you live in 
called off-line world communication is dominated by two way, real time 
communication, ie. you and a friend talking. This conversation is being operated 
in two directions, with questions/answers being talked about right away. Now in 
the computer sphere, a two way communication mediated by shared signals for 
beginning/ending conversations is called SYNCHRONOUS communication. Synchronous 
communication is like normal human/animal conversation. This form of 
communication relies on shared signals for starting and stopping. Examples of 
this communication would be like your browser sending a msg to a host and the 
host sends you something, a packet or a file. Programs which deal with this 
communication are software found on your box, Cu-Cms and RealVideo are some, 
which allow internet users with properly equipped hosts to converse with other 
internet users through a video channel. Problems arise in this form of 
communication, because as both of us know if you don't have the bandwidth, you 
will be staring at a video box with images that are jerky and stroboscopic 
(images which look like garbage). <BR><BR>When a communication exchange does not 
rely on shared signals for starting and stopping, this communication is called 
ASYNCHRONOUS communication. Now your probably confused but don't be. This form 
of communication seen online is characterized by long waits for responses. This 
communication is seen in email messages which take some people forever to answer 
back. This doesn't have anything to do with the servers or the bandwidth, but 
has to do with the human being on the other side. Email messages are delivered 
in a matter of seconds, but there is no guarantee that an intended recipient 
will be ready and waiting to reply as soon as your message is received. So the 
reason for this is that it pays to think about what your are saying and how your 
saying because it will affect the outcome of the asynchronous communication. 
<BR><BR><BR><B><FONT color=#ffffff><A name=charge></A>6: Who is in 
Charge?</FONT></B><BR><BR><BR>Your probably wondering, yeah I always wanted an 
answer to that question, so explain to me plz. hehe! <BR><BR>Okay I am not going 
to lie to you, questions about Internet management and maintenance are very 
boring so bare with me. You might also want to ask who pays for all this? Who 
fixes it when it messes up? Who is responsible for keeping everything working? 
Who makes the decisions about the future of this wonderful tool? Well I'll 
answer everything right here. <BR><BR>As I explained in the previous parts of 
this text, the net is composed of thousands of smaller networks that are 
independent from one another, remember the heterarchical structure,heh. Now 
these smaller networks are managed by corporations, government agencies and 
universities with different hardware platforms and different network 
technologies. Now you see that I am going back and all these small and large 
networks are held together by a wonderful glue called TCP/IP. But I see your 
going to ask, okay, cool but what holds it together administratively, like how 
can this huge tool have no central authority? Okay let me answer your question, 
remember when i told you that the Internet was made by scientists and 
programmers, well those guys have always pushed the spirit of this wonderful 
tool. So when these guys made up TCP/IP they made it public so that TCP/IP could 
be placed on any hardware platform. Now the Department of Defense had a large 
part in this deal but like the Department of Defense, the university researchers 
also did a lot, and like the rest they also made their finding public. By doing 
this anyone who had access to the internet, could access these documents and put 
their own influence into the development of the net. Now you might think that 
all this public stuff is done with, well not. This way of life is still managed 
by a group that oversees the continuing growth of the Internet, this group is 
called, INTERNET SOCIETY (ISOC). This organization oversees a number of smaller 
groups also pursuing the growth of the net. These groups are: <BR><BR><B>- 
Disaster Assistance Committee <BR>- Internet Operations Forum <BR>- Internet 
Architecture Board (IAB) <BR>- Internet Engineering Task Force (IETF) <BR>- 
Internet Assigned Number Authority (IANA) <BR>- Internet Engineering Steering 
Group (IESG) <BR>- Internet Research Task Force (IRTF) <BR>- k-12 Committee 
<BR></B><FONT color=#ffffff></FONT><BR>ISOC has no sanction or governmental 
power so it operates as a resource for ppl who want to participate in the growth 
of the net. <BR><BR>The Internet's high-speed backbone is a key component of the 
net, and many different organizations have said they are responsible for 
maintaining the backbone. In the 70's, research parties funded by the Advanced 
Research Projects Agency (ARPA) were given access to ARPAnet. In the late 70's, 
the National Science Foundation (NSF) joined with ARPA to create a network that 
would be more available for computer scientists in the US. NSF then gave birth 
to CSnet in 1979. In 1982, a gateway was established between ARPAnet/CSnet, 
which demonstrated the viability of a network of networks like a small version 
of the Internet. After the joining of ARPAnet/CSnet, the term "INTERNET" was 
then adopted. <BR><BR>By 1983, more networks began to do the same thing by 
expanding/establishing their own user communities. In San Francisco, FidoNet 
connected FidoBBS (Bulletin Board Systems) across the nation so that many users 
of local bulletin boards could exchange messages by email/discussion groups. In 
the same year, the Department of Defense switched all of its military networks 
to the TCP/IP protocol. By then, TCP/IP software was only included in all UNIX 
software distros out of the University of California at Berkley. UNIX was the 
operating system of choice for computer scientist, and it still is, so by doing 
this a huge jump was put in Internet expansion. <BR><BR>BY 1985 the Internet was 
further expanded when NSF became a leader in network communication and they got 
funding from Congress to join 100 more universities to the Internet. By doing 
this NSF then connected five supercomputer sites in a new network called NSFnet. 
With all these costs and further spending the Federal Government, soon realized 
it couldn't afford to subsidize the Internet. So now it became a private 
industry. So the firms which made up the NSFnet backbone (IBM, MCI, MERIT) 
created a nonprofit company called Advanced Networks and Services (ANS). Then in 
1992, ANS built a new backbone, ANSnet, with 30 times the bandwidth of the old 
NSFnet backbone. ANSnet is the current backbone for the Internet and the first 
one not maintained by the government but by private companies. <BR><BR>Now since 
your probably bored and confused, let me finish off, since no federally 
sponsored organization oversees everything, there are some which monitor some 
parts. Lets look at Federal Communication Commission (FCC) they don't have any 
authority over the net, but they do regulate the billing practices of telephone 
companies. This is really cool, cause the FCC does not allow phone companies to 
bill ppl for digital communication differently than they do for voice 
communication. So the main deal is this, the net is operated by small spheres 
and ppl who impose on themselves to censor stuff or to protect ppl from the bad 
sides of the net. <BR><BR><BR><B><FONT color=#ffffff><A name=future></A>7: The 
future of the Internet <BR></FONT></B><FONT color=#ffffff></FONT><BR><BR>Well I 
am going to let you do some work now. Since you just read the info on the net 
how big you think the info on Internet2 is going to be. let me give you a hint, 
it is going to be big. At the moment, a new upgraded version of the internet is 
in development, and its going to be called Internet 2 or simply I2. This will be 
a heaven when its complete so with out further interruption I have made a site 
dedicated to Internet 2. The site is good enough and is still up to date. Chk 
out the links for further news on it. The url of the site is <A 
href="http://i2.virtualave.net/">http://i2.virtualave.net/</A> ahh man i forgot 
to kill the banners, well enjoy!!!<BR><BR><BR><B><FONT color=#ffffff><A 
name=read></A>8: Further reading </FONT></B><BR><BR><BR>Okay I have chosen some 
books if you want to learn more, cause you know in 3 decades i summarized them 
in 7 or 8 pages so i think you might want to read more. <BR><BR>Good books to 
read. <BR><BR>Where Wizards Stay up Late, by Katie Hafner and matthew Lyon. 
Simon and shuster, New York, NY, 1996. (304 pages) <BR><BR>Being Digital, by 
Nicholas Negroponte. Vintage Books, New York, Ny, 1995. (255 pages) <BR><BR>The 
Internet 1997 Unleashed, by Jill Ellsworth and Billy Baron (Eds)Sams.net 
Publishing, Indianapolis, IN, 1996. (1,269 pages) </FONT></P></BODY></HTML>