ITC542 Internetworking with TCP/IP: Maximum Transmission Units

1. The Maximum Transmission Units (MTUs) range from 296 to 65,535 based on specific protocol used by the system. What would be the advantages of having a large MTU? What would be the advantages of having a small MTU?
   

2. Compare and contrast CSMA/CD with CSMA/CA.
   

3. What is the purpose of including the IP header and the first 8 bytes of datagram data in the error reporting ICMP messages?
   

4. Which ICMP messages contain part of the IP datagram? Why is this needed?
   

5. An organisation has been allocated the following block of classless addresses by its ISP. 160.70.60.12/28 List all the addresses in this range and identify those that can be used by the hosts (total host number and their IP address), the network address, the subnet mask and the direct broadcast address. Show your calculations as detail as possible
   

6. A router running RIP has a routing table with 20 entries.

1. a) How many periodic times are needed to handle this table? Justify your answer. 
2. b) How many expiration times are needed to handle this table? Justify your answer.
3. c) How many garbage collection times are needed to handle this table if five routers are invalid? Justify your answer.
   

7. As the network administrator for a growing Internet service provider (ISP), you want to make efficient use of your network addresses. One of the network addresses Internet Assigned Numbers Authority (IANA) assigned to you a classless network of 160.50.1.1/23. You have decided to use the network addresses to satisfy the IP address requirements of 16 corporate customers who need between 18 and 30 host addresses each. Without using a subnet calculator, calculate a subnet mask that meets their needs. List the subnet mask and all subnetwork addresses the mask will create. Show the detail calculation.
   

8. You work at a help desk and have just received a call from an employee who says she can’t access network resources. You want the employee to view her IP address configuration. You wrote an e-mail to the employee, explaining what command-line program to use and how she can use it to find the information you need. After following your instructions, the employee tells you that her IP address is 169.254.14.11 with the subnet mask 255.255.0.0. What conclusion can you make from this information?
   

9. As the network administrator for a growing Internet service provider (ISP), you want to make efficient use of your network addresses. One of the network addresses Internet Assigned Numbers Authority (IANA) assigned to you is a Class C network of 192.168.1.0. You have decided to use the addresses in this Class C network to satisfy the IP address requirements of 16 corporate customers who need between 10 and 14 addresses each. Without using a subnet calculator, calculate a subnet mask that meets their needs. List the subnet mask and all subnetwork addresses the mask will create. Show detail calculation for each of your output
   

10. An organization is granted a block of addresses with the beginning address 14.24.74.0/24. The organization needs to have 3 subblocks of addresses to use in its three subnets as shown below:

 ? O ne subblock of 120 addresses.

? O ne subblock of 60 addresses.

?One subblock of 10 addresses.

 Answer the following questions and show detail calculation for each –

1. Calculate total number of IP address, first and last addresses of given block.
2. Calculate subnet mask, subnetwork address and broadcast address of each subnets

Answers: