CSCI 547 Computer Networks Final Exam
Fall 2005
Closed book, closed
notes. Some questions have
multiple answers!
Name:___________________________________
1.(6 points) IEEE 802 protocols
Match the following
802 protocols with a description. Draw lines between them.
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802.1 802.2 802.3 802.5 802.3u 802.3z |
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100M bps Ethernet Token ring & Physical layer 1000M bps Ethernet Higher layer interface to 802 protocols Logical Link Control CSMA/CD & Physical layer |
2.(2 points) Industry group—mark
the answer
_________ are
special-interest-industry groups that quickly test, evaluate, and standardize new
technologies.
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a. |
Regulatory agencies |
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b. |
Standard organizations |
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c. |
Forums |
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d. |
Technical societies |
3.(4 points) Physical Layer's functions
What aspects do we
need to define in a physical layer? Choose all that apply.
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a. |
Application Program Interface(API) |
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b. |
Mechanical connections |
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c. |
Error detection codes |
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d. |
Electrical specifications |
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e. |
Functional characteristics of the interface |
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f. |
Flow control mechanism |
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g. |
Procedural aspects |
4.(1 points) Dotted decimal notation
Given the following
IP address in binary, what is its dotted decimal equivalent? 10000100 11110001
10011110 00100001
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a. |
132.243.148.34 |
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b. |
123.142.150.33 |
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c. |
132.241.158.33 |
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d. |
132.241.156.30 |
5.(6 points) Subnet masks
For the subnetting scheme which allows all 0’s and all 1’s subnetids(such as CIDR), choose all the possible subnet
masks.
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a. |
64 |
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b. |
128 |
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c. |
192 |
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d. |
224 |
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e. |
240 |
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f. |
242 |
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g. |
248 |
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h. |
250 |
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i. |
252 |
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j. |
254 |
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j. |
255 |
6.(1 points) Address class
Identify the class
of the following IP address: 224.2.3.4
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a. |
Class A |
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b. |
Class B |
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c. |
Class C |
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d. |
Class D |
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e. |
Class E |
7.(2 points) Devices
with more than one IP addresses
A device has more than one IP addresses. This device could be ____. Choose all that apply.
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a. |
a computer |
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b. |
a bridge |
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c. |
a router |
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d. |
a hub |
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e. |
a repeater |
8.(2 points) Identify IP address
Identify the
following IP address: 132.241.255.255
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a. |
host IP address |
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b. |
direct broadcast address |
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c. |
limited broadcast address |
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d. |
network address |
9.(4 points) Getting IP address
A host can get its
IP address from its server by using _____ as the source address and ____ as the
destination address.
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a. |
255.255.255.255 ; 127.0.0.1 |
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b. |
127.127.127.127 ; 0.0.0.0 |
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c. |
0.0.0.0 ; 255.255.255.255 |
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d. |
255.255.255.255 ; 0.0.0.0 |
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e. |
none of the above |
10.(3 points) Through a
router?
A host with IP
address 132.241.158.98 with subnet mask of 255.255.255.224 sends a message
to a host with IP address 132.241.158.48. Does the message travel through any
router?
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a. |
Yes |
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b. |
No |
11.(3 points) Through a
router?
A host with IP
address 132.241.158.35 and subnet mask 255.255.255.240 sends a message to a host
with IP address 132.241.158.52. Does the message travel through any router?
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a. |
Yes |
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b. |
No |
12.(4 points) Supernet mask
Which one should be
the "supernet mask" to combine 32 class C network addresses?
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a. |
255.255.255.192 |
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b. |
255.255.252.0 |
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c. |
255.255.248.0 |
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d. |
255.255.240.0 |
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e. |
255.255.224.0 |
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e. |
255.255.192.0 |
13.( 2 points)Default mask
Which of the
following is the default subnet mask(before any subnetting) for the address
132.241.158.33?
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a. |
255.0.0.0 |
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b. |
255.255.0.0 |
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c. |
255.255.255.0 |
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d. |
255.255.255.224 |
14.(3 points) How many hosts
per subnet?
A subnet mask of
255.255.255.248 allows how many hostids per subnet?
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a. |
30 |
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b. |
14 |
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c. |
6 |
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d. |
2 |
15.(1 points) Additional Fragmentations
When a router
cannot deliver an IP datagram in its original size, the router fragments IP
datagram into several fragments. Can a fragmented datagram be fragmented again?
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a. |
Yes |
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b. |
No |
16.(1 points) Assembly of Fragments
Who is responsible
for the assembly of fragments?
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a. |
A router on destination network |
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b. |
The destination host |
17.(4 points) Usage of
MTU
table
A router uses a
table called "MTU table". MTU stands for Maximum Transfer Unit.
Describe how a router uses this table.
18.(6 points) Port vs Socket
(a) Point out the
difference(s) between "ports" and "sockets".
(b) What is
“Winsock”?
19.(4 points) Connection-Oriented Service
List the things(at
least 4) that a connection-Oriented service should do to provide its service.
20.(3 POINTS) Why 3 way handshake?
When TCP makes a
connection, it uses 3 way handshaking mechanism. Describe why we need 3 way
handshaking?
21.(6 points) Solutions to IP address space?
IP address space
for IPv4 is running out. What are the three solutions to the problem? Briefly describe each of them.
22.(5 points) Distance vector vs link state
What are the main
differences between "Distance vector" and "
23.(8 points) How to serve multiple clients?
Describe how a TCP/IP
server program can accommodate multiple client connections. Include the words:
Well-known port number, Ephemeral port number, blocking(waiting) state, create
a child process, queue-size.
24.(7 points) Draw a
diagram comparing the protocol architecture between OSI and TCP/IP and label
all the layers.
25.(3 points) One of
the reason that Ethernet dominates the LAN protocols is”backward
compatibility”. Describe how the “backward compatibility” is achieved.
26.(5 points) ARP
Describe how ARP works including the terms; ARP cache, ARP request, ARP reply, MAC address, IP address.
27.(4 points) OSI
Discuss why OSI model
is still discussed in almost every aspect of modern computer network protocols.