Department of Computer
Network Architecture and Programming
Homework 3 (Total 40 pts)
Due in class on Thursday February
Please hand in a hardcopy of your homework in a folder,
which has your name and course number, in class on Thursday Feb. 16th, 2006. (Always keep
a copy of the homework you hand in). Each solution must include all
calculations and an explanation of why the given solution is correct. In
particular, write complete sentences. A correct answer without an explanation
is worth no credit. No late homework will be accepted. Electronic preparation
of your solutions is mandatory.
Q1. (5 pts)
TCP assumes an MSS
of 536 if it does not receive an MSS option
from the peer. Why is that value used?
Q2. (5 pts) Do port addresses need to be
universally unique? Why or why not?
Q3. (10 pts) A TCP
Connection is using a window size of 10,000 bytes, and the previous acknowledgment
number was 22,001. It receives a segment with acknowledgment number 24,001. Draw
a diagram to show the situation of the window before and after.
Q4. (10 pts) In the TCP
acknowledgment mechanism, a lost acknowledgment (sent by the receiving TCP)
may not even be noticed by the source TCP. Comment
on the validity of this statement explaining your answer. In addition, give a
numerical example supporting your answer.
Q5. (10 pts) A source TCP
can receive a zero window-size advertisement from the receiving TCP.
Explain what is the source TCP
reaction to such reception?
Do you see a potential problem in such
situation? Explain your answer?
Research how TCP
designers handled this problem. List any references you consult.