Network Routing and Switching Assignment-

Instructions

You must do this assignment individually, that is, on your own.

Type all your answers in the Template for Your Answers Section of this document and upload only that template. You could do that by copying the Template section into a new Word document for uploading.  Answers that are not typed into the Template for Your Answers section may not be marked, or may be returned to you for re-typing and re-submission late penalties will apply.

You must show all your working that is, steps you took to arrive at your answers. Write your answers in your own words to avoid potential plagiarism and copyright violations.

Question 1 - Routing table construction

Given the following network, construct the routing table for routers R2 and R3.  Be sure to include the default route.

Question 2 - Allocating subnets from a block

ABEC Pty Ltd (a public company) has been granted a block of addresses starting with the address 172.154.60.0/24.

a) Calculate the total number of addresses in this block. Show your calculation.

b) The company has decided to distribute the addresses on a departmental basis, with Dept#1 requesting 120 addresses, Dept#2 requiring 60 addresses, Dept#3 needing 30 addresses and Dept#4 wanting 12 addresses.

Create the 4 subnets for the company.  For each subnet, list the subblock address along with its subnet mask in CIDR format.  Show your calculations for all subnets.

c) How many addresses are left unallocated? Show your calculation.

Question 3 - Fragmentation

An Ethernet packet 1,500 bytes long arrives at a router, which determines that the next destination is an X.25 network.  Do the following, being sure to show your calculations and explain your reasons.

a) Assuming that the router decides to fragment the packet into 3 fragments, determine the size of each fragment, and identify their starting byte and end byte.

b) Calculate the fragmentation offset for each fragment. 

c) Under what specific condition would the router decide not to fragment the packet and in that case how would the packet be treated?  Be as precise as possible in your answer.

Question 4 - Advanced routing study

Research and review appropriate materials, including the textbook, and answer the first two questions (a & b).

a) Define the terms and discuss the relationship between Autonomous Systems, Inter-domain routing, and Intra-domain routing. 

b) Identify the major routing protocols associated with Inter-domain and Intra-domain routing and list their similarities and differences. Finish by commenting on why we need different protocols for Inter-domain and Intra-domain routing. 

Study the two articles listed below both is freely available on the Internet. You may use other references in addition to these, as needed.  Then answer the remaining 3 questions (c, d & e). 

c) Briefly summarize in your own words the problems with current routing methods that the authors have identified. 

d) Contrast and compare the concepts of embedded routing and extensible routing. 

e) How does the proposal of Routing As A Service (RAAS or just RAS) address the problems with current routing methods?

Referencing:  List all references and use proper in-text citation using the Harvard referencing convention. Remember that diagrams also need to be cited.  Marks will be deducted on a per-question basis for not adhering to referencing standards.

The two articles for questions 3 & 5 (both articles have the same title):

Routing as a Service by K.Lakshminarayanan et al can be found at:

http://www.eecs.berkeley.edu/Pubs/TechRpts/2006/EECS-2006-19.pdf

Routing as a Service by K.Lakshminarayanan, Stoica, and Shenker can be found at:

https://www.cs.princeton.edu/~jrex/teaching/spring2005/reading/ras04.pdf

Question 5 - IPv6 Packets

Case: An IPv6 packet consists of a base header and a TCP segment.   The data is 128,000 bytes long (jumbo payload).

a) Draw a diagram of this packet that shows and labels all the base header fields, the Hop-by-hop Extension header fields, and the TCP segment fields.

b) Place a correct value in the following fields in the base header with a brief explanation for the value you selected

Version; Payload Length;  Next Header;  Hop limit:  Source Address;  Destination Address

Do not type answers here: type it in the Answers Template provided.

Suggested sources of information:

Forouzan (textbook) chapter 27-

http://ptgmedia.pearsoncmg.com/imprint_downloads/cisco/promotions/clnwebinars/9781587143137_ch02.pdf

http://www.cu.ipv6tf.org/literatura/chap3.pdf.

TEMPLATE FOR YOUR ANSWERS

Type your answers in this section in the spaces provided

Question Number

Mark

allocated

Mark earned

Question 1: (9 marks)

Routing table of router R2:

Mask

Network address

Next-hop address

Interface