CST311 - Module 4

What did I learn in the fifth/sixth week of CST311?

This module was also combined, as there is a programming assignment for the fifth week, while having the sixth week assigned to the module's information for the fourth chapter. Therefore, the module went over the data plane of the network layer. Basically, it is responsible for forwarding packets across networks, which is defined by the services provided by the network layer, such as packet delivery, fragmentation, reassembly, buffer management, and packet scheduling. Furthermore, the module distinguished between forwarding and routing, while going over the internal components of a router, such as input/output ports, switching, and forwarding table. In the end, the module introduced network address translation and middleboxes, which modify traffic for security or performance, while generalizing forwarding and SDN.

The next programming assignment that was done in the fifth week was over a TCP chat service and extra credit. Basically, it's a simplified version of a TCP data transfer over an unreliable network using python sockets. This was to simulate the behavior of the RDT 3.0 protocol, which handled packet loss and corruption using checksums, ACKs/NAKs, and timeouts with retransmissions.