Lecture 2: Introduction (Jan 25)

Today, Dr. Gunes made an introduction to Network Systems in this lecture. He gave the definition of "network". He explained and compared multi-access and point to point networks. Then, he talked about different types of networks(according to their sizes) which are Local Area Network (LAN), Wide Area Network (WAN) and Metropolitan Area Network (MAN). And, he compared these different types of networks according to their reliability and speed. Then, he went over the Internet. He talked about the components of the Internet. He showed the roughly hierarchical architecture of the Internet. He explained the differences between the Tier-1,2 and 3 ISPs. For example, a university network is Tier-3 type. Then, he talked about Internet service providers and Internet design goals and principles. An interesting thing was that there is no mention of security among the Internet design goals. Finally, he explained why we use layering, the advantages of layering and gave some layered system examples. For example, federal express is a good example of layered systems. In conclusion, I highly benefited from this lecture, since it was a good introduction to Network Systems.