EJERCICIOS DEL LIBRO:
TCP/IP Protocol Suite.
Behrouz A. Forouzan.
ISBN 0-256-24166-X
1ra edición.
CHAPTER 12 - PRACTICE SET (12.15 Section)
Multiple choice.
1.TCP lies between the _________ and the __________ layers of the TCP/IP protocol suite.
a. application, UDP
b. application, transport
c. application, network
d. network, datalink.
2. IP is responsible for __________ communication while TCP is responsable for ________
communication.
a. host-to-host, process-to-process.
b. process-to-process, host-to-host.
c. process-to-process, network-to-network.
d. network-to-network, process-to-process.
3. A host can be identified by ____ while a program running on the host can be identified by ___.
a. an IP address, a port number.
b. a port number, an IP address.
c. an IP address, a host address.
d. an IP address, a well-known port.
4. The _______ address uniquely identifies a running application program.
a. IP address.
b. host
c. NIC
d. socket.
5. If a segment carries data along with an acknowledgment, this is called ______.
a. backpacking.
b. piggybacking.
c. piggypacking.
d. mother´s helper.
6. The ________ field is used to order packets of a message.
a. urgen pointer.
b. checksum.
c. sequence number.
d. acknowledgment number.
7. The ______ field is used for error detection.
a. urgent pointer.
b. checksum.
c. sequence number.
d. acknowledgment number.
8. Multiply the header length field by _____ to find the total number of bytes in the TCP header.
a. 2
b. 4
c. 6
d. 8
9. Urgent data requires the urgent pointer field as well as the URG bit int the _____ field.
a. control
b. offset
c. sequence number
d. reserved
10. Which of the following is not a valid acknowledgment number?
a. 0
b. 1
c. 232-1
d. 232
11. Which field indicates the length of the TCP header?
a. window
b. acknowledgment
c. header length
d. control
12. The options field of the TCP header ranges from 0 to _________ bytes.
a. 10
b. 20
c. 40
d. 232
15. Which option defines the maximum number of bytes in a TCP segment?
a. maximum segment size
b. window scale factor.
c. timestamp
d. no operation
20. TCP uses _______ for error detection.
a. checksum
b. acknowledgment
c. time-out
d. all of the above
21. An ACK number of 1,000 means ________ .
a. 999 bytes have been successfully received.
b. 1,000 bytes have been successfully received.
c. segment 999 has been received.
d. segment 1,000 has been received.
22. The ________ timer prevents a long idle connection between two TCPs.
a. retransmission
b. persistence
c. keepalive
d. time-waited
23. The _________ timer is needed to handle the zero window-size advertisement.
a. retransmission
b. persistence
c. keepalive
d. time-waited
25. The _________ timer is used in the termination phase.
a. retransmission
b. persistence
c. keepalive
d. time-waited
26. The _________ timer keeps track of the time between the sending of a segment and the
receipt of an acknowledgment.
a. retransmission
b. persistence
c. keepalive
d. time-waited
27. A server issues _________ open while a client issues _________ open.
a. an active, a passive
b. a passive, an active
c. an ephemeral, a well-known
d. a well-known, an ephemeral
28. Connection establishment involves a ____________ handshake, connection termination
involves a ___________ handshake.
a. one-way, two-way
b. two-way, three-way
c. three-way, three-way
d. three-way, tour-way
Exercises.
38. What is the maximum size of the TCP header?
39. What is the minimum size of the TCP header?
40. If the value of HLEN is 0111, how many bytes of option are included in the segment?
41. What can you say about the TCP segment in which the value of the control field is one of the
following:
a. 000000
b. 000001
c. 010001
d. 000100
e. 000010
f. 010010
43. TCP opens a connection using an inicial sequence number (ISN) of 14,534. The other party
opens the connection with an ISN of 21,732. Show the three TCP segment during the connection
establishment.
47. A TCP connection is using a window size of 10,000 bytes and the previous acknowledgment
number was 22,001. It receives a segment that acknowledges bytes 24,001. Draw a diagram to
show the situation of the window before and after.
56. Show the entries for the header of a TCP segment that carries a message from a FTP client to
a FTP server. Fill the checksum field with 0s. Choose an appropriate ephemeral port number and
the correct well-known port number. The length of data is 40 bytes.
60. The following is a dump of a TCP header in hexadecimal format.
05320017 00000001 00000000 500207FF 00000000
a.
b.
c.
d.
e.
f.
g.
What is the source port number?
What is the destination port number?
What is the sequence number?
What is the acknowledgment number?
What is the length of the header?
What is the type of the segment?
What is the window size?