Below are samples of multiple choice questions. In the real exam you will have to answer them on the computer scoring sheet provided and you will need a soft lead (HB) pencil.
A lot of questions in this exam are based on the Fig. 1 on the last page. The correct answers are marked “x”
1. Process P0 on the node abc.cpsc.ucalgary.ca wants to communicate with a process P1
on the node xyz.it.sait.ab.ca. (see Fig. 1) Process P0 must create:
a. Fully Qualified Domain Name
b. IP Address
c. Socket x
d. Frame
2. The message from process P0 will be passed to which OSI layer?
a. Application
b. Transport x
c. Network
d. Datalink
3. In a situation similar to Fig. 1, process P0 is uniquely identified on the whole network
by:
a. Port number
b. IP address
c. NIC card address
d. Combination of a. and b. x
4. Eventually the frame will be transmitted by abc.cpsc.ucalgary.ca. This frame will be
seen by:
a. All the nodes in U of C
b. All the nodes on the subnet x
c. Router only
d. All the nodes in U of C and SAIT
5. Router R0 has:
a. One IP address and two NIC cards
b. Two IP addresses and two NIC cards x
c. More than two IP addresses and two NIC cards
d. None of the above
6. When the router R0 receives a frame it will be able to recognize the following:
Does the frame belongs to U of C?
If yes which subnet does it belong to?
The router can do that because it knows:
a. The portion of IP address which identifies U of C
b. The U of C netmask
c. Both a. and b. x
d. Both a. and b. plus port number of the application which created the frame
7. IP protocol is running on which OSI layer?
a. Application
b. Transport
c. Network x
d. Datalink
8. IP protocol can be described as:
a. Connectionless, unacknowledged x
b. Connectionless, acknowledged
c. Connection-oriented
d. Connection-oriented, unacknowledged
9. TCP and UDP protocols are running on which OSI layer?
a. Application
b. Transport x
c. Network
d. Datalink
10. TCP protocol can be described as:
a. Connectionless, unacknowledged
b. Connectionless, acknowledged
c. Connection-oriented x
d. Connection-oriented, unacknowledged
11. UDP protocol can be described as:
a. Connectionless, unacknowledged x
b. Connectionless, acknowledged
c. Connection-oriented
d. Connection-oriented, unacknowledged
12. With respect to Fig. 1, P0 initiates the communication with P1. In this situation:
a. P0 is a client and P1 is a server x
b. P0 is a server and P1 is a client
c. Cannot say
Examples of short answer questions:
1. Presume a transmission line of the length of 1 Km with one node on each end. (see
the fig. below)
1 Km
<------------------------------------------->
---------------------------------------------
| |
----- -----
| | | |
| | | |
----- -----
A B
Node A transmits a frame of the size 1500 bytes to node B. The speed of
transmission is 10 Gbit / sec. The frame propagates on the line with the
speed of light (300 000 Km / sec). Calculate the following (in power of 10
notation):
a. The time interval from the time node A start to transmit the frame till
node B can start to send the reply. Presume no delay in node B.
Answer: ...4.5 * 10**-6............[ sec ] [2 points]
b. Time interval from the time node A starts to transmit the frame till
node A starts to receive the reply from node B.
Answer: .....7.8 * 10 ** -6...........[ sec ] [2 points ]
c. How many bytes must the frame have in order to fill in the whole line ?
That is, node B will receive the first byte of the frame while node A is still
transmitting the last byte of the frame.
Answer: .....4166.................. [bytes] [2 points]
2. IP Address: 136.159.6.13
Netmask: 255.255.252.0
What is the Network and Host address?
Network: 136.159.4
Host: 2.13
3. CIDR address is as follows: 194.24.16.0 / 20
What is the smallest and largest address belonging to this site?
How many hosts?
Smallest: 194.24.16.0
Largest: 194.24.31.255
# of hosts: 2**12 – 2
4. Consider the output from the following "netstat" command: (display this question using MS Explorer )
|
netstat -r
|
||||||
|
Kernel IP routing table |
||||||
|
Destination |
Gateway |
Flags |
MSS |
Window |
irtt |
Iface |
|
192.168.66.1 |
* |
UH |
40 |
0 |
0 |
eth1 |
|
136.159.6.0 |
* |
U |
40 |
0 |
0 |
eth0 |
|
192.168.66.0 |
* |
U |
40 |
0 |
0 |
eth1 |
|
127.0.0.0 |
* |
U |
40 |
0 |
0 |
lo |
|
default |
136.159.6.1 |
UG |
40 |
0 |
0 |
eth0
|
Answer the following:
a) How many subnets is this node connected to? ............2................... [1 point]
b) What is (are) the subnet number(s) of subnet(s) connected to this node? Presume the Netmask to be 255.255.255.0
136.159.6.0
............192.168.66.0................................. [2 points]
c) What is the IP address of the router responsible for sending messages to the outside world?
............136.159.6.1................................... [1 point]
5. Consider the following TCP exchange:
With respect to the TCP header format on p. 537 of the book fill in the Sequence
number and Acknowledgement number for each TCP header of the exchange
