April 2000
AN215 : ADVANCED NETWORKING

QUESTION 2

Total Marks: 15 Marks

• Question 1
• Question 3
• Question 4
• Question 5
• Cover Page

Click to access
SUGGESTED SOLUTIONS
for Question 2

The network layer may provide services using packet switching,message switching or circuit switching.

(a)What is the purpose of these switching techniques?[2 marks ]

(b)Describe the operation of message switching.[6 marks ]

(c)Is message switching suitable for interactive traffic?Explain your answer [3 marks ]

(d)A 4096 byte message,which has to be sent.You have a choice between using a virtual circuit (VC) or a datagram network.The addressing verheads involved in the VC is a 2 byte VC identifier per packet that it takes 2 seconds to establish a logical path.On the other hand,the overheads in the datagram packet is 16 bytes.You may ignore any other overheads.Assuming it takes one second to transfer one packet across the network.Which type of network is more efficient Justify your choice.State any assumptions you wish to make.(Show all workings)[4 marks ]