CCN – revision lecture

Exam 2 hours long 3 out of 5 questions (25points each question, maximum 75 points) Past exams visible via portal (just enter the module code)

Module contents and structure Part 4: applications Part 3: internetworking Part 2: packet transmission Part 1: data transmission

Part 1: data transmission Transmission media; Local asynchronous communication (RS-232); Long distance communication (modems and carriers)

Part 2: packet transmission Packets, frames and error detection Local area networks (LANs) Hardware addressing Extending LANS: Fiber Modems, repeaters, bridges and switches; WAN Technologies and routing Network ownership and service paradigm Protocols and layering

Part 3: internetworking Concepts, architecture and protocols IP addresses Binding protocol addresses (ARP) IP Datagrams and datagram forwarding IP encapsulations, fragmentation and reassembly The future of IP TCP (reliable transport service)

Part 4: applications Client-server interaction The socket interface Example applications

Feedback Most students attempt questions 1,2 and 3 with mixed results Least number of student attempt question 5 typically with very good results Not many students attempt question 4 with mixed results

Typical mistakes Incomplete answers: e.g. giving definitions but not comparisons as in transmission media and bit rate/baud rate questions Providing diagrams or formulas without explanations (e.g RS-232, modulation, Shannon theorem) Many incorrect answers usually in the area of routing, next hop and bridges Vague answers on the questions such as the purpose of routers and TCP protocol stack

Any questions?