ECET 465 Exciting Results / snaptutorial.com

1. ECET 465 Week 1 Homework (Chapters 1 and 5) For more classes visit www.snaptutorial.com ECET 465 Week 1 Homework (Chapters 1 and 5) ************************************ ECET 465 Week 1 iLab For more classes visit www.snaptutorial.com Scenario/Summary: One’s understanding of network protocols can often be greatly deepened by “seeing protocols in action” and by “playing around with protocols” – observing the sequence of messages exchanged between two protocol

2. entities, delving down into the details of protocol operation, and causing protocols to perform certain actions and then observing these actions and their consequences. This can be done in simulated scenarios or in a “real” network environment such as the Internet. The Java applets that accompany your text take the first approach. In these Wireshark labs, we’ll take the latter approach. You’ll be running various network applications in different scenarios using a computer on your desk, at home, or in a lab. You’ll observe the network protocols in your computer “in action,” interacting and exchanging messages with protocol entities executing elsewhere in the Internet. Thus, you and your computer will be an integral part of these “live” labs. You’ll observe, and you’ll learn, by doing. ************************************ ECET 465 Week 2 Homework (Chapters 4 and 5) For more classes visit www.snaptutorial.com ECET 465 Homework week2 Chapter 4 Review Questions

3. R2. What are the two most important network layer functions in a datagram network? What are the three most important network layer functions in a virtual circuit network? R4. Do the routers in to set up a virtual circuit over four links: link A, link B, link C, and link D. Suppose that each of these links is currently carrying two other virtual circuits, and the VC numbers of these other VCs are as follows: ************************************ ECET 465 Week 2 iLab IP Protocol For more classes visit www.snaptutorial.com Week 2 - IP Protocol This lab is due on Sunday, at the end of Week 2. Scenario/Summary: In this lab, we’ll investigate the IP protocol, focusing on the IP datagram. We’ll do so by analyzing a trace of IP datagrams sent and received by an execution of the tracerouteprogram (the traceroute

4. program itself is explored in more detail in the Wireshark ICMP lab). We’ll investigate the various fields in the IP datagram and study IP fragmentation in detail. ************************************ ECET 465 Week 3 Homework (Chapters 3 and 4) For more classes visit www.snaptutorial.com Chapter 3 Review Questions R4. Describe why an application developer might choose to run an application over UDP rather than TCP. R6. Is it possible for an application to enjoy reliable data transfer even when the application runs over UDP? If so, how? R8. Suppose that a Web server runs in Host C on port 80. Suppose this Web server uses persistent connections, and is currently receiving requests from two different Hosts, A and B. Are all of the requests being sent through the same socket at Host C? If they are being passed through different sockets, do both of the sockets have port 80?

5. in a multicast group. Given this, how can multicast applications learn the identities of the hosts that are participating in a multicast group? ************************************ ECET 465 Week 3 iLab Router Configuration For more classes visit www.snaptutorial.com ECET 465 Week 3 iLab Router Configuration ************************************ ECET 465 Week 4 Course Project For more classes visit www.snaptutorial.com

6. The week 4 class project is a simulation of major components and their setup configurations that would be needed to create a network. More specifically, we will be using routers, switches, hosts, and different connections between them for physically transmitting. We are also going to look at the addressing needs. The project uses the Cisco ConfigMaker for the entire duration of the project . . . which, for me, involved a bit of a learning curve all by itself. What is not covered would be some of the personal settings that would be setup on an individual computer (as in: if we were looking at different operating systems such as Windows XP, 7, 8, or perhaps a Mac). ************************************ ECET 465 Week 4 iLab TCP For more classes visit www.snaptutorial.com TCP Lab: Scenario/Summary: In this lab, we’ll investigate the behavior of TCP in detail. We’ll do so by analyzing a trace of the TCP segments sent and received in transferring a 150KB file (containing the

7. text of Lewis Carrol’s Alice’s Adventures in Wonderland) from your computer to a remote server. We’ll study TCP’s use of sequence and acknowledgement numbers for providing reliable data transfer; we’ll see TCP’s congestion control algorithm – slow start and congestion avoidance –in action; and we’ll look at TCP’s receiver- advertised flow control mechanism. We’ll also briefly consider TCP connection setup and we’ll investigate the performance (throughput and round-trip time) of the TCP connection between your computer and the server. Before beginning this lab, you’ll probably want to review Sections 3.5 and 3.7 in the text. Deliverables: Lab Report with overview, activities, and summary Answers to questions included in lab Captured screenshots of data iLab Steps Step 1: Capturing a bulk TCP transfer from your computer to a remote server Before beginning our exploration of TCP, we’ll need to use Wireshark trace in Wireshark; see Footnote 2). Whenever possible,

8. when answering a question, you should hand in a printout of the packet(s) within the trace that you used to answer the question asked. Annotate the printout to explain your answer. To print a packet, use File->Print, choose Selected Packet Only, choose Packet Summary Line, and select the minimum amount of packet detail that you need to answer the question. ************************************ ECET 465 Week 5 Homework (Chapter 2 Review Questions) For more classes visit www.snaptutorial.com Chapter 2 Review Questions SECTION 2.1 R.1. List five nonproprietary Internet applications and the application- layer protocols that they use.

9. R.8 List the four broad classes of services that a transport protocol can provide. For each of the service classes, indicate if either UDP or TCP (or both) provides such a service. SECTION 2.6 R.25 Skype uses P2P techniques for two important functions. What are they? SECTIONS 2.7–2.8 R.28 For the client-server application over TCP described inSection 2.7, why must the server program be executed before the client program? For the client-server application over UDP described inSection 2.8, why may the client program be executed before the server program? ************************************ ECET 465 Week 5 iLab Client Server Applications For more classes visit www.snaptutorial.com We know that HTTP, FTP, and SMTP all use TCP. DNS and SNMP use UDP. TCP offers reliable transport, while UDP is “best-effort.” When you design your own distributed applications, you will need to decide

10. whether to use TCP or UDP. We are going to study differences between TCP and UDP implementations of a very simple application. Deliverables: Provide a report that includes an overview, highlights the process, answers the questions in the lab body, and provides your conclusion. In addition to what you have learned, the conclusions should include the following: Compare the TCP- and UDP-embedded applications. You should mention differences in the code. Base this on your understanding of the connection-oriented service of TCP, as compared to connectionless UDP. ************************************ ECET 465 Week 7 Homework (Chapters 6 Questions and Problems) For more classes visit www.snaptutorial.com Homework – Chapter 6 Questions: R1, R3, R5, R8, R14, R16, R18, R19, R21 Chapter 6 Problems: P6, P7, P9, P10, P11, P14

11. ************************************ ECET 465 Week 7 iLab 802.11 Wireless Network Protocol For more classes visit www.snaptutorial.com In this lab, we investigate the 802.11 wireless network protocol. A trace of captured 802.11 frames is provided to analyze. This trace was collected using AirPcap and Wireshark running on a computer in the home network of one of the authors, consisting of a Linksys 802.11g combined access point/router, with two wired PCs and one wireless host PC attached to the access point/router. In this trace file, frames captured on Channel 6 can be seen. The wireless host activities taken in the trace file are: The host is already associated with the 30 Munroe St AP when the trace begins. At t = 24.82, the host makes an HTTP request to http://gaia.cs.umass.edu/wireshark-labs/alice.txt. The IP address of gaia.cs.umass.edu is 128.119.245.12.

12. At t = 32.82, the host makes an HTTP request to http://www.cs.umass.edu, whose IP address is 128.119.240.19. At t = 49.58, the host disconnects from the 30 Munroe St AP and attempts to connect to the linksys_ses_24086 AP. This is not an open access point, and so the host is eventually unable to connect to this AP. At t = 63.0, the host gives up trying to associate with the linksys_ses_24086 AP, and associates again with the 30 Munroe St access point. ************************************ ECET 465 Week 7 iLab For more classes visit www.snaptutorial.com ECET 465 Week 7 iLab ************************************