Wide Area Networks Part 2

Question 1

1
What does the x in xDSL represent?

a/ Wire type

b/ Transmission speed

c/ DSL type

d/ Download speed

Answer 1

1

c/ The x in xDSL represents the different letters that refer to the DSL flavors. xDSLs use high-frequency signals, whereas regular phone calls use low-frequency signals over the same lines.

Question 2

2
Which is not a type of xDSL?

a/ ADSL

b/ HDSL

c/ SONET

d/ SDSL

Answer 2

2

c/ ADSL, HDSL, SDSL, VDSL or VHDSL, and VDSL2 are all common xDSL types. Synchronous Optical Network (SONET) is the standard for synchronous data transmission on optical fiber.

Question 3

3
What does the acronym DOCSIS stand for?

a/ Data over cable service interface spectrum

b/ Data over cable systems Internet specification

c/ Data over cable service Internet specification

d/ Data over cable service interface specifications

Answer 3

d/ DOCSIS stands for data over cable service Interface Specifications. All cable modems and like devices have to measure up to this standard.

Question 4

4
What is the bandwidth for OC-12?

a/1.544 Mbps

b/ 45 Mbps

c/ 622 Mbps

d/ 1000 Mbps

Answer 4

4

c/ Optical carrier 12 has speeds up to 622 Mbps.

Question 5

5
Which WAN protocol utilizes cell-switching technology?

a/ Frame Relay

b/ ISDN

c/ ATM

d/ RIP

Answer 5

5

c/ ATM uses a high-speed cell-switching technology that can handle data as well as real-time voice and video. The ATM protocol breaks up transmitted data into 53-byte cells.

Question 6

6
Which WAN protocol utilizes packet-switched technology?

a/ Frame Relay

b/ ISDN

c/ ATM

d/ RIP

Answer 6

6

a/ Frame Relay is the frame WAN technology in which variable-length packets are transmitted by switching.

Question 7

7
What is the CIR in Frame Relay?

a/ Virtual circuit that is established when data needs to be transmitted

b/Maximum speed at which the Frame Relay interface can transmit

c/ Rate at which the Frame Relay switch guarantees to transfer data

d/ Rate at which the Frame Relay switch agrees to receive data

Answer 7

7

c/ The committed information rate (CIR) is the rate, in bits per second, at which the Frame Relay switch guarantees to transfer data.

Question 8

8

You are having DSL Internet connection issues and time-outs. You check the interface on your router and notice a lot of input errors. What could the problem be?

a/ CSU/DSU

b/ Arcade

c/ Duplex configuration

d/Clocking is down

Answer 8

8

c/ We’re thinking in terms of a DSL, so a CSU/DSU is not used, nor is a demarc. If clocking was down, your Internet would be completely down. Input errors could be indicative of a duplex issue.

Question 9

9

Which part of a SIP trunk is the responsibility of the provider?

a/ Private domain

b/ Community domain

c/ Public domain

d/ External domain

Answer 9

9

c/ The public domain (responsibility of the provider) is the part of the network that allows access into the PSTN (Public Switched Telephone Network) or PLMN (Public Land Mobile Network).

Question 10

10
Which technology can eliminate VPN traffic between remote sites traversing the hub?

a/ DMVPN

b/ SIP trunk

c/ DMDW

d/ DNSSEC

Answer 10

10

a/ Benefits of Dynamic Multi-point VPN include elimination of traffic between remote sites traversing the hub, elimination of additional bandwidth requirements at the hub, elimination of additional network delays, conservation of WAN bandwidth, lower costs for VPN circuits, and increased resiliency and redundancy.