Assignment 1

1. Which is better, circuit switching or packet switching?

2. Read all of the site,

3. How does the value of a network vary as the number of participants increases? Why?

4. Internet protocols are defined by an open process. What are the advantages and disadvantages of this process, compared with a design carried out by a single company?

5. Suppose the Internet has not been invented yet but everyone wants one, so you are in charge of the design. The first question that you are asked is about addressing. What will you need to have addresses for? Which of these addresses need to be fixed in hardware and which can be changed by an administrator?

Assignment 2

1. Comer 2.3

2. If a new network is added to the Internet shown of slide 12 of Lecture 2, how many routers need to know all the Ethernet addresses of the hosts connected to the new network?

3. Comer 4.3

4. What is the most critical resource on the Internet?

Assignment 3

1. Comer 5.6

2. Comer 5.9

3. Comer 6.3

4. Comer 6.4

5. Comer 6.6

Assignment 4

1. Comer 7.1

2. Comer 8.3

3. Run traceroute for,, and, and explain the results.

4. Run ping for the three hosts above and explain the results.

5. Comer 9.3

6. Comer 9.6

7. Comer 9.8

Assignment 5

1. Comer 10.2

2. Comer 10.11

3. Comer 11.6

4. Comer 11.18

Assignment 7

1. Comer 14.5

2. Comer 14.6

3. Comer 14.17

4. Comer 14.18

5. What is the most up-to-date RFC for the Internet routing protocol? How does one find the most recent RFC for any Internet protocol?

6. Comer 14.8

7. Suppose Ethernet did not have any built-in multicast capability. Describe how a host would send an IP multicast address, giving the destination and source addresses in the frame and datagram. And describe how a multicast router would deliver a multicast datagram to a local host, giving the frame and datagram source and destination addresses.

8. In class we discussed how Multicast routers need to count the number of members in each multicast group on their network so that they know when they no longer have a member of a group because the final host has left the group. Read the relevant RFC--state which one that is--and explain whether our conclusion last week is correct, based on what the RFC says.

Assignment 8

1. Comer 23.3

2. Comer 23.5

3. Comer 23.13

4. Comer 23.15

Assignment 9

1. Comer 22.19

2. Comer 22.15

3. Comer 22.16

4. Comer 24.9. Explain the answer.

5. Comer 24.8. Show the TELNET session.

6. Comer 24.11

From now on, all assignments must be submitted as html documents.

Assignment 10

1. Comer 25.1

2. Comer 25.2

3. Comer 25.10

4. Comer 25.13

5. Comer 27.4

6. Comer 27.9

Assignment 11

Make an new invention that capitalizes on many of the following trends:

1. Electronic devices (EDs) are getting smaller

2. An ED can know where it is in 3 dimensions at all times

3. An ED can know the time and temperature at all times

4. An ED can be made very rugged to withstand 10 Gs or more of shock

5. An ED uses very little power, can power itself for a long time

6. An ED can have capture still and moving images

7. An ED can connect to a LAN of other local EDs or to the Internet

8. An ED can receive any part of the electronic spectrum

9. Any ED can have a permanent (v6) IP address

Your invention must make use of trend #7. Describe your invention and how it is an improvement over what is used now.

Assignment 7

1. Under what circumstances would I want to employ MPLS?

2. Give three different protocols that rely on router exchanges of information that are based on spf. Briefly explain.

3. Would I ever want to use a VPN inside a single company? Under what circumstances? Why?

4. What are the major factors that make multicasting routing difficult?

Assignment 8

1. Use TELNET to access an SMTP server to pick up an email. Show the dialogue.

2. Locate, download and install an FTP client with a GUI. Use it to download a file. Also do the same thing using FTP with a command-line dialogue. Show the dialogue. Which do you prefer?

3. What is an ad hoc network? What are its uses? How does it work?

Assignment 9

1. Consider the three principal name spaces on the Internet: MAC addresses, IP addresses and domain names. Make a table comparing them with regard to their important characteristics.

2. While sending an IP datagram from host A to host B, and a return datagram from host B to host A, where A and B are on different networks,

a) What will be the source and destination IP addresses on the datagram sent from host A?

b) What will be the destination MAC address on the frame containing the datagram sent by host A?

c) Which addresses will change by the time the information reaches host B, and which ones will remain the same?

d) What will be the source and destination IP addresses on the datagram sent from host B?

e) What will be the destination MAC address on the frame containing the datagram sent by host B?

f) Which addresses will change by the time the information reaches host A, and which will remain the same?

3. There are some common ideas that we see again and again in Internet protocols. Describe four important ones.

4. Providing reliable communications is performed at only one level of the Internet protocol stack. Does this provide any important benefits? Why do you think this approach was adopted?

5. Suppose it was your job to redesign the entire Internet. You are free to replace hardware and software throughout the world as you decide. As you start your design work, think about the issue of name spaces that you considered in the first question. What is the smallest number of basic name spaces could you have on your new Internet? Which ones would you have, and why? What would have to be changed to get to your new design with the minimum number of name spaces?