Question # 2.

a. A client sends a 500 byte request message to a service, which produces a response containing 5000 bytes. Estimate the total time to complete the request in each of the following cases, with the performance assumptions listed below:

i) Using a connectionless communication protocol;

ii) Using a connection-oriented communication;

iii) The server process is in the same machine as the client.

[Latency per packet (local or remote, incurred on both send and receive): 5 milliseconds

Connection setup time (TCP only): 5 milliseconds

Data transfer gate: 5 megabits per second

MTU. 1 S00 bytes

SeYver request processing time: 3 milliseconds

Assume that the network is lightly loaded.)

b. Discuss the use of connectionless (UDP) and connection-oriented (TCP) communication for of each of the following application:

1. Mail access protocols (for example, POP3);

2. Voice over IP;

3. Web browsing;

4. Global Positioning System (GPS).

5. File Transfer Protocol

6. DNS Protocol

7. YouTube

8. Remote Procedure Call

c. A sequence of packets are transmitted back to back from a source to a destination through a wide area network.

i) Is it possible for these packets to be received at destination in an order that is different form that in which it is transmitted? Explain.

ii) If the sour and destination are in the same local area network, can these packets arrive to the destination out of order?