Telecom Systems Assignment
Based on Telecommunications Essentials by Lillian Goleniewski
Chapter 7
Wide Area Networking
Student’s Name: ___________________________________________
1
1.
What is a WAN?
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1
2.
What was the initial application for frame relay?
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1
3.
What is a VPN?
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1
4.
WANs can be constructed over packet switched networks, but not circuit switched
networks. [True, False]
2
5.
What is the advantage of using a multi-point leased line?
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Telecom
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2
5.
What is the disadvantage of using a multi-point leased line?
____________________________________________________________________
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1
7.
Leased lines can operate at DDS speeds but not SDH. [True, False]
1
8.
DDS is [faster, slower] than SONET.
2
9.
What is the ones density rule?
____________________________________________________________________
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1
10.
If a leased line goes down, the network recovers almost immediately. [True,
False]
1
11.
What is the minimum bit rate usually specified to support video conferencing?
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2
12.
What is a fractional service?
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2
13.
What is dark fiber?
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Telecom
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2
15.
What does an intelligent multiplexer do?
____________________________________________________________________
____________________________________________________________________
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3
16.
List three applications for digital cross-connects.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
1
17.
What is the approximate bit rate for an OC-3?
____________________________________________________________________
1
18.
ISDN cannot be used in a circuit-switched LAN. [True, False]
1
19.
PRI ISDN is used for residential service while BRI is used for business service.
[True, False]
3
20.
List three applications for N-ISDN.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
1
21.
X.25 can handle both voice and video. [True, False]
1
22.
The performance of packet-switched networks is not affected by the speed of
transmission facilities between switches. [True, False]
1
23.
Frame relay is a [connection, connectionless] packet service.
1
24.
Packets on connectionless networks have [more, less] overhead than packets on
connection oriented networks.
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1
25.
X25 networks perform error checking at every intermediate node. [True, False]
1
26.
The packet size in a frame relay network is [fixed, variable].
3
27.
List three advantages for X.25.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
3
28.
List three disadvantages for X.25.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
1
29.
Frame relay performs a lot of error control. [True, False]
1
30.
Frame relay is gradually being phase out. [True, False]
1
31.
The frame relay interface takes the native data stream no matter what the protocol.
[True, False]
1
32.
Frame relay includes a CRC function. [True, False]
1
33.
Frame relay [includes, does not include] a discard eligibility field.
1
34.
Subscribers specify the CIR (committed information rate) in a frame relay
network. [True, False]
1
35.
Frame relay [has, has essentially no] provisions for the control of latencies and
losses.
1
36.
What is VoFR?
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3
37.
List three advantages for frame relay.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
3
38.
List three disadvantages for frame relay.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
2
39.
What is the purpose of ATM?
____________________________________________________________________
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1
40.
Approximately 80% to 85% of all Internet backbones and frame relay networks
have ATM at their core. [True, False]
1
41.
ATM is much cheaper than gigabit Ethernet in LAN environments. [True, False]
1
42.
ATM cells are [5, 48, 53] octets long.
1
43.
ATM is not a connection-oriented network. [True, False]
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3
44.
List the three main layers in ATM.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
1
45.
ATM adaptation layer [1, 2, 3] is intended to support isochronous variable-bit-rate
services such as packetized video.
2
46.
What is an ATM virtual channel?
____________________________________________________________________
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2
47.
What is an ATM virtual path?
____________________________________________________________________
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3
48.
List three advantages for ATM.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
October 25, 2005
Telecom
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3
49.
List three disadvantages for ATM.
1. __________________________________________________________________
2. __________________________________________________________________
3. __________________________________________________________________
October 25, 2005
Telecom
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