SIT202 : Computer Networks - IT Assignment

Internal Code : MAS975

IT Assignment

Questions : 1. Consider the problem of transferring a large file via the web: a) Identify how many networks are illustrated and what topologies is/are used in each network identified. Explain how you identified the networks and topologies in your answer. b) For each of the five devices illustrated, indicate which layers of the TCP/IP protocol suite are certain to be found on that device and briefly explain why. c) In the Week 1 slides / prescribed reading, it is mentioned that addressing is required at all layers except the physical layer. If this is true, explain how the physical layer will be able to deliver/direct the data to its intended destination. Refer to the above scenario/network when explaining your answer. 2. a) Given that electromagnetic waves can travel at the speed of light, briefly explain how different signals can arrive at different times when transmitted at the same time. Consider both wired and wireless media in your answer. b) Consider a digital signalling approach that uses only two voltage levels to represent binary data and achieves a data rate of 1Mbps. Explain how increasing the number of voltage levels could potentially increase the data rate and briefly discuss the potential problems that may be encountered. c) A network administrator has identified that several paths throughout the organisation’s network are experiencing significant latency. Given that latency consists of propagation time, transmission time, queuing time, and processing delay, discuss how each of these could potentially be reduced, addressing the identified problem. d) Consider the Manchester and Differential Manchester encoding schemes. i. Using the same input of 8 bits, draw an illustration of both schemes. For the input sequence, you may choose any 8 bits however must include both 1 and 0 bits. ii. Explain how these schemes achieve self-synchronization. iii. Explain the relationship between DC components and baseline wandering and how these schemes resolve this problem. e) Consider the frequency-division multiplexing and time-division multiplexing techniques. Give an example where these two techniques could be used at the same time and explain how they are used.