The time has come…

The time has finally arrived: the Internet was created!!! Not today, (obviously!), but in our seminar’s reading of Hafner and Lyon’s book! This week’s reading was by far the one that most interested me, as it involved the steps from the ARPANET to the real Internet.

The creation of the Ethernet, in my opinion, was one of the major advances in this whole process we have been studying. The ARPANET pioneers wanted to get rid of the AT&T Network (by the way, this is not the AT&T phone company we use today!) as their phone lines were extremely expensive. Many local networks were arising, and the thought now was to find a way to connect these local networks and allow communication between them. Networks such as the SATNET, CSNET and ALOHANET were being developed and this was an incentive for people to build different networks for the local. The question was: how would these networks communicate to each other? Taking the ALOHANET and the ARPANET as examples, both had different interfaces, transmission rates and packet sizes (the ALOHANET was for broadcasting with radios while the ARPANET was for routing and has IMPs and host computers). Their solution came down to a simple word: a gateway.

The gateway was a machine with a software that made it look like a host to the ARPANET IMPs and it would be connected to the radio waves at ALOHANET. This means another level of indirection was added: the gateway would be connected to an IMP on ARPA and radio waves on ALOHA. It did not focus on the content or the complexity of the content being transferred, it assumed things that came before were reliable and therefore its job was simply to transfer the information (end-to-end reliability). So, the Ethernet actually originated from the already-existing ALOHANET.

The protocol used began as TCP (Transmission Control Protocol) and then it ended up splitting into TCP/IP (Internet Protocol). After this split, the TCP would be responsible for “breaking up messages into datagrams, reassembling them at the other end, detecting errors, resending anything that got lost, and putting packets back in the right order”, while the Internet Protocol would be responsible for routing individual diagrams. In this way, the huge function that the TCP had before was distributed and this shifted reliability onto the hosts.

So, this brings us to the distinction between what was the “internet” and the “Internet”: the first meant any network using TCP/OP while the second meant the public, federally subsidised network that was made up of many linked networks (all running TCP/IP protocols). And this, ladies and gentlemen, was how this Internet was finally created (!!!!).

Later on in the seminar, we moved our discussion to a topic that I personally had never thought about. Would you imagine that typing in a set of numbers into your browser could lead you to a webpage? Well, I didn’t, until Dean Smith and Professor Waldo explained the DNS – Domain Name System – in which each webpage has its set of characters corresponding to its type of protocol, name server and top level domain. It’s amazing to think about how many things we use nowadays on the Internet, without knowing the actual work behind them. The good part is, though, that the seminar will help me with this issue by teaching me new things as we go along!

One thought on “The time has come…

  1. I like the energy in your entry. You got me excited. Now that you’ve started to think about how things work behind the scenes in the Internet, you might consider how routing actually works on the Internet. Think about the different entities (routers, gateways, hosts). What do they have to know? How is what they know first known? Does it need to get updated? How often? Don’t worry about how it exactly works, but think about what generally needs to happen. I bet you’ll get close to how it actually works. Ask your friends what they think!

Leave a Reply

Your email address will not be published. Required fields are marked *