如对您有帮助，欢迎下载支持，谢谢！
思科网络学院 CCNA 4 练习题和答案 English FormD EWAN v4.0 Chapter 1 .2.4 WAN Switching Concepts Assessment Item:
What is an advantage of packet-switched technology over circuit-switched technology?
Packet-switched networks are less susceptible to jitter than circuit-switched networks are.
Packet-switched networks can efficiently use multiple routes inside a service provider network. Packet-switched networks do not require an expensive permanent connection to each endpoint. Packet-switched networks usually experience lower latency than circuit-switched networks experience.
Reset View Learner Response
Scoring Rule for: correctness of response 2 points for Option 2
This item references content from the following areas:
CCNA Exploration
1.2.3 WAN Data Link Layer Concepts Assessment Item:
Which statement about WAN protocols is correct?
ATM differs from other WAN protocols in that it uses variably sized packets. Most WAN protocols use HDLC or a variant of HDLC as a framing mechanism. The frame header consists of the frame check sequence and cyclic redundancy check.
ISDN differs from Frame Relay, HDLC, and ATM in that it is packet-switched rather than circuit-switched technology.
Reset
Scoring Rule for: correctness of response 2 points for Option 2
This item references content from the following areas:
CCNA Exploration
1
如对您有帮助，欢迎下载支持，谢谢！
1.2.4 WAN Switching Concepts Assessment Item:
Why is the call setup time of a circuit-switched WAN implementation considered a drawback?
Routing protocols are incompatible with this function. It restricts the communication sent to voice traffic only. A telephone must be used to initially start transferring data. Data cannot be transferred until a circuit has been established.
Reset
Scoring Rule for: correctness of response 2 points for Option 4
Assessment Item:
Which statement is true about the differences between a WAN and a LAN?
WANs generally support higher bandwidth than LANs support.
A WAN link typically traverses shorter geographic distances than a LAN link traverses.
A WAN often relies on the services of carriers, such as telephone or cable companies, but a LAN does not.
All WAN implementations generally use the same Layer 2 protocol but there are many accepted LAN Layer 2 protocols in use.
Reset
Scoring Rule for: correctness of response 2 points for Option 3
1.2.2 WAN Physical Layer Concepts Assessment Item:
Which statement is true about data connectivity between a customer and a service provider?
Normally the CSU/DSU is the designated demarcation point for the service provider but not the customer.
2
如对您有帮助，欢迎下载支持，谢谢！
The segment between the demarcation point and the central office is known as the \ The local loop is the segment between the CSU/DSU and the serial port on a router. Putting data on the local loop is the responsibility of the DTE.
Reset
Scoring Rule for: correctness of response 2 points for Option 2
1.1.3 The Evolving Network Model Assessment Item:
Which statement is true of the functionality of the layers in the hierarchical network model?
The purpose of the access layer is to provide very high bandwidth communications between network devices.
Most security screening to prevent unauthorized entry to the network happens at the core layer. Untrusted external connections are segmented from the rest of the network at all three levels. The distribution layer aggregates WAN connections at the edge of the campus.
Reset
Scoring Rule for: correctness of response 2 points for Option 4
1.2.2 WAN Physical Layer Concepts Assessment Item:
Which two devices are commonly used as data communications equipment? (Choose two.)
modem router CSU/DSU ISDN switch Ethernet switch
Reset
3