CST 311 Week 5

CST 311 Week 5

This week was all about the Network Layer of the Internet Protocol stack. The concepts of routing and forwarding were discussed and contrasted. I learned about a router's forwarding table and how it uses the longest prefix matching rule to determine the link interface from a packet's destination IP address. We then delved deep into the inner workings of a router. IP datagrams and IP addressing were also analyzed in depth. The concepts of how DHCP is used to obtain a host IP address were explored and analyzed during our lab in which we were able to see the DHCP messages that were used for a host to obtain an IP address. The DHCP discover, offer, request, and ACK are part of this 4 way process for a host to obtain an IP address. Finally NAT or Network Address Translation was explored in how it allows for an internal network to hide details of its network with the outside world. NAT is also controversial.

This week was filled with a ton of  new information and I feel I will have to revisit it again thoroughly before our next final.

CST 311 Week 4

CST 311 Week 4

         This week was a short week in which we got to focus on studying for our midterm. We learned about socket programming with UDP and TCP and the key differences in programming for the two protocols. With UDP socket programming, no handshaking is necessary to establish a connection. The sender explicitly attachesIP destination address and port number to each packet. The receiver extracts sender IP address and port number from the received packet. Wtih TCP programming the client must contact the server. The server must have a "welcome" door that welcomes a clients contact. When a client is contacted, TCP server creates a new server socket to communicate with that particular client. Python code was explored in how client and server applications are coded for UDP and TCP socket programming.

CST 311 Week 3

CST 311 Week 3

I found this week to be challenging as it was a lot of new material. I found the videos to help tremendously as the reading was a lot to take in and it was good to learn from a different form. This week we learned all about the transport layer of networks. We learned about the specifics of how UDP and TCP transport data on the transport layer. The concepts of multiplexing and demultiplexing were examined. We also learned how TCP and even UDP implement reliable data transfer along the transport layer.

CST 311 Week 2

CST 311 Week 2

This week was all about the application layer of the Internet protocol stack. Before this week I had a limited knowledge of HTTP, cookies, SMTP, and Peer to Peer. I learned that HTTP connections can be both persistent or non-persistent and the differences between the two. Before this week I understood the concept of cookies but did not know exactly how they worked. This week's lesson helped to expand my knowledge on the subject. Web caches can be used to make web browsing more efficient from the client end. The amount of "conversations" that occur for small amounts of data is neat to see with WireShark and a bigger appreciation for the application layer has been realized through my studies this week. We owe a lot to the scientists and researchers who have created this technology in which most people take for granted not knowing really what is involved behind the scenes in the various Internet networks.

CST 311 Week 1

CST 311 Week 1

This week I learned about the basic structure of the internet and the networks within it. It is now understood that the network edge consists of clients and servers and the network core is the network of networks that consists of interconnected routers. The idea of packet switching and how it drives the flow of information across networks was also introduced. I learned about packet delay and the various processes that effect packet delay suck as nodal processing, queueing delay, transmission delay, and propagation delay. Formulas for figuring these four delay processes were introduced. The throughput of networks was studied and also how to find the throughput of a given network. Finally we learned about the internet protocol stack and the layers within: application, transport, network, link, physical.

I felt this was a good introduction to the basic structure of how networks and the network core work. It forms a good basis for what I am sure will be a more in depth analysis of computer networks. I found the history of computer networks to be fascinating as far as how they have changed communication so much in so little time considering that for thousands of years forms of communication did not change very much.