MN503 Overview of Internetworking Assignment 1, T1 2016 Assignment 1: Individual Assignment – Submission in MS Word format with Video file. Submission Due: Sunday 1st May'16 23:55 hrs (Week 6) in the specified folder on Moodle. Total Marks = 150 (15% of total assessment) Purpose of the assessment: The purpose of this assignment is to allow the students to perform minor research and critical thinking on topics of UDP, TCP and DNS protocols experimentally by using Wireshark in Part A and Riverbed based network simulation in Part B. Hands-on practical experience will facilitate the students to increase the understanding of these protocols and the concept of network simulations. You need to fully answer Part A and Part B sections. Description of the assessment: Go to http://www.wireshark.org/download.html and download and install the Wireshark binary for your own computer. In the labs you have already used Wireshark so far. Case Study – Part A As a Network Analyst for DataTech corporation that specialises in data analysis you want to evaluate your companies key networks. DataTech wants you to evaluate UDP, TCP, and DNS protocols on your network. Various types of data transfer such as voice, video or data could occur on your network. You need to use suitable applications so as to satisfy the need for capturing packets of each of the above stated protocols. As you need to generate a report for the higher management which comprises of technical as well as non-technical personnel so you need to ensure that your report is clear, cohesive and contains relevant screenshots with suitable annotations to explain your answers. Furthermore, you need to generate a 2 min (video with audio) clip to briefly explain any of the experiments that you perform to answer any one of the questions for UDP or TCP or DNS protocol listed below. The video clip must briefly capture your face, your audio explanation and the experiment being conducted on the computer monitor (screen). First answer ALL the following critical thinking questions listed below. Then perform the experiments using Wireshark for UDP, TCP and DNS and answer ALL the questions listed in Parts 1 to 3. Critical Thinking Questions: 1) What is the purpose of a Network Interface card (NIC). On what layer of the OSI model is it based. Why? 2) Does a computer need to use both MAC address and an IP address? Justify your answer. Download and install the Wireshark software: MN503 Overview of Internetworking P a g e | 2 of 5 3) Does reliable transfer of data imply no errors in data transmission? Justify your answer. 4) Can the Wireshark protocol analyser be used to generate packets for different protocol types? Justify your answer. 5) List the different purposes for which a protocol analyser such as a Wireshark can be used. PART 1 – UDP Protocol Use an application that generates UDP packets. Run Wireshark and capture packets for around 1-2 min. Stop Wireshark and use UDP in the filter bar to list only the UDP packets. Whenever possible, when answering a question below, you should place a screenshot of the packet within the trace that you used to answer the question asked. Annotate the screenshot to explain your answer. 1) What application have you used to generate the UDP packets? Select one UDP packet from your trace. From this packet, determine how many fields there are in the UDP header. Name these fields. 2) From the capture determine the data rate of the UDP packets? Explain what you need to do in Wireshark to obtain this automatically? 3) The value in the Length field is the length of what? Verify your claim with your captured UDP packet. 4) What field in the UDP packet identifies the application in the end host? 5) Is the purpose of checksum field in a UDP packet to offer reliability? Justify your answer. 6) Would you use UDP for the reliable transportation of real-time or non-real time traffic? Justify your answer. PART 2 – TCP Generate TCP packets by using a suitable application. Capture the generated TCP packets by using Wireshark. Answer the following questions. 1) What is the purpose of TCP protocol? How does it differ from UDP protocol? 2) For a captured TCP packet, what is the IP address and TCP port number used by the client (source) computer and the destination computer. Annotate this on a screen shot. 3) What is the purpose of TCP port number? How it is used? 4) Why do ICMP (ping) packets do not have a TCP port number? Justify your answer. MN503 Overview of Internetworking P a g e | 3 of 5 5) From the TCP capture, what is the sequence number of the TCP SYN segment that is used to initiate the TCP connection between the client computer and the destination? How is TCP SYN segment found? Annotate it on the screen shot. 6) From the TCP capture, calculate the Round trip time (RTT) for sending a TCP segment. How is the RTT obtained? Part 3 – DNS Protocol 1) Explain briefly what DNS protocol is? What is the IP address of your local DNS server? Provide a screenshot to indicate your answer on it. 2) How would you flush your local DNS server? Use a web browser to visit any website and capture and filter the DNS packets on Wireshark. What are the ports used in the DNS message? Provide a screenshot to support your answer. MN503 Overview of Internetworking P a g e | 4 of 5 PART B- Riverbed Modeler based Simulation Experiments DataTech Consulting wants you to create a 10base-T hub star based Ethernet in the Riverbed Modeler using Rapid Configuration. You can use Ethernet_wkstn as the periphery node model i.e. as the hosts/Ethernet stations, and 10base T link model to connect hosts to the hub. Use interarrival time between packets to be exponentially distributed with a mean of 0.03 sec. First have 10 ethernet node stations connected to it. Evaluate the performance of the 10base-T Ethernet in terms of throughput vs delay for packet sizes of constant distribution for each of the following two packet sizes: 512 bytes, and 1500 bytes. Make sure you apply the same traffic distribution to each of the hosts/Ethernet stations. Then repeat the same for 20, 30, 40, 50, 60, and 70 stations. Use graphs wherever required in the questions below: (i) In your opinion what is the purpose of network simulation? What are the different simulation tools available (max up to 4) and state their advantages and disadvantages. (ii) Capture the graph of throughput vs delay for one of the two packet sizes and explain the nature (shape) of the throughput vs delay graph as the load on the Ethernet is increased. What is the load in this case? Put the final graph in the report. (iii) From the graph of throughput vs delay for 1500 bytes packet size and stations ranging from 10 up to 70 in increments of 10 how would you determine the optimal number of Ethernet stations that could be supported on the 10base T Ethernet hub? Put the final graph in the report. (iv) What is the nature of the data traffic generated in the above Ethernet network. Justify your answer. (v) What are the sources of the delay in the throughput vs delay graph? State and briefly explain each of them. Submission guidelines: Your assignment should be completed according to the General Guidelines for Presentation of Academic Work. 1. successful completion of required tasks • clear understanding of the answers provided. • attempt all questions. • required technologies or equipment • comparison with others (if applicable) • configuration (if applicable) • troubleshooting (if applicable) 2. quality of figures/tables • clear and well organised screeshots/drawings/table • meaningful names • Referencing MN503 Overview of Internetworking P a g e | 5 of 5 3. accompanying documentation including • a front page - indicating your name and student ID. • Summary with a statement of what has been completed • Acknowledgement of the names of all people (including other students and people outside of the university) who have assisted you. • table of contents and page numbers • Conclusion • Appendix (if applicable) 4. Referencing • list of references used (IEEE style) 5. The assignment must be submitted online in MS Word format in the specified folder on Moodle by the due date and time. Extensions: Requests for an extension, accompanied by supporting documentation, must be received by the student in writing before 3 working days from the due date else penalties may apply for late submission without an approved extension. Special consideration form is available in MIT reception. Penalties: Academic misconduct such as cheating and plagiarism may incur penalties ranging from a reduced result to program exclusion. Marking criteria (MN503): Marks are allocated as follows: Section to be included in the report Description of the section Marks Content- Part A Correctness and understanding of the answers 19 Questions x 4 marks = 76 Video clip (max 2 min duration) 4 Marks Part B Correctness and understanding of the answers 5 X 10 = 50 Marks Diagrams (Screenshots) Content supported by Figures , Tables, Charts etc. 10 Marks Documentation front page, formatting, page numbering, table of contents 5 Marks Reference Material referenced in this research work 5 Marks Reference style Use IEEE referencing style only Poor writing Inadequate structure, careless presentation, poor referencing technique or not using at all -5 MN503 Overview of Internetworking P a g e | 6 of 5 Plagiarism Type of plagiarism - Copy from other student - Copy from internet source/textbook - Copy from other sources -150 Total 150 Marks Marking Rubrics Description of the section Excellent Good Unsatisfactory Content relevant answers with Understanding Limited relevant answers with average understanding Poor answrers/Lack of understanding Diagrams Sufficient diagrams are included to support the content Diagrams limited No diagrams included Documentation Comply to the submission guidelines Comply partially to the submission guidelines Submission guidelines not followed Reference Relevant resources are included Included resources are limited No references included Reference - Computer Networks, A Top-down Approach, 6 th ed., J.F. Kurose and K.W. Ross, AddisonWesley/Pearson, 2012