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Question |
Max. |
Current |
|
Part I. True and False |
10 pts. |
|
|
1-5 |
20pts |
|
|
6-10 |
20 pts |
|
|
11-15 |
20 pts. |
|
|
16-19 |
20 pts |
|
|
20-21 |
10 pts. |
|
|
Total: |
100pts |
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__ An IP router
when routing a packet modifies the source hardware address.
__ Routers need routing tables but hosts do not need them.
__ Distance Vector routing converges faster
than Link State routing.
__ In RIP a
distance of 15 means infinite distance
__ In Traceroute, the first packet sent has a TTL of 0.
__ A TCP acknowledgment acknowledges all bytes in sequence sent since
the connection was opened.
__ ssh could be used to forward TCP traffic through a secure channel.
__ MIME stands for Multipurpose Internet Media Extensions.
__ SOAP stands for Simple Object Access protocol
__ A packet fragment
can be fragmented.
1. Explain why Hosts (and not only routers) have routing tables.
2. Explain the sequence of events that causes an ICMP redirect to be
produced.
3. Explain
what XDR stands for and why it is necessary in RPCs.
4. Write
the equations used to estimate a) the average round trip time, b)
variance and c) the retransmission timer in TCP Adaptive
Retransmission.
5. Explain
how TCP flow control works.
6.
Enumerate the parameters that a host needs to be connected to the
Internet.
7. Explain
the differences between HTTP1.0 and HTTP 1.1
8.
Explain the TCP Fast Retransmission mechanism and how it speeds up TCP.
9. What are the advantages and disadvantages of using CGI vs. Application Servers when implementing web applications.
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10. Assume that a TCP connection with parameters <src-ip-addr, src-port,dest-ip-addr, dest-port> is initiated by a host behind a NAT box with IP address IPnat. Explain how NAT works using these parameters.
11.
Explain what does VPN stands for and how it works.
12. Explain why TCP is not used for streaming.
13.
Explain what does DHCP stand for, and how it works.
14.
Explain how traceroute works.
15. Explain why opening a TCP connection using a three-way handshake
takes only 3 packets but closing a connection using three way
hand-shake takes 4 packets.
16.
Explain what is multimedia streaming.
17.
Explain what the jitter-buffer used for.
18.
Explain when proxy objects are garbage collected in Java RMI.
19.
(8 pts) Write
down the TCP Header format and its fields. Show also the size of each
of the fields.
20.
If an IP telephone crashes before telling the directory server that it
is going down it will leave the entry registered in the directory
server eventhough the telephone is no longer running. How could you
solve this problem?
21.
Enumerate the threads needed to implement an IP telephone.