1.
Which networking device is typically used to concentrate the dial-in and dial-out traffic of multiple users to and from anetwork?
Correct Answer
B. Access server
Explanation
An access server is typically used to concentrate the dial-in and dial-out traffic of multiple users to and from a network. This device allows multiple users to connect to the network through a single point of access, providing centralized control and management of the dial-in and dial-out traffic. It acts as a gateway between the users and the network, allowing them to access resources and services.
2.
Which WAN technology uses a fixed payload of 48 bytes and is transported across both switched and permanent virtualcircuits?
Correct Answer
A. ATM
Explanation
ATM (Asynchronous Transfer Mode) is the correct answer because it uses a fixed payload of 48 bytes, known as a cell, for data transmission. These cells are transported across both switched and permanent virtual circuits, making it a suitable WAN technology for various applications. ISDN (Integrated Services Digital Network), Frame Relay, and metro Ethernet do not have a fixed payload size of 48 bytes and may not be transported across both switched and permanent virtual circuits.
3.
Which term describes a device that will put data on the local loop?
Correct Answer
C. DCE
Explanation
A DCE (Data Circuit-terminating Equipment) is a device that connects a customer's premises to a telecommunications network. It is responsible for putting data on the local loop, which is the physical connection between the customer's location and the service provider's network. The DCE converts the data into a format that can be transmitted over the local loop, allowing communication between the customer's equipment (such as a computer) and the network. Therefore, the term "DCE" accurately describes a device that puts data on the local loop.
4.
Which switching type will allow the communication devices in the provider network to be shared and only allocated to anindividual subscriber during data transfer?
Correct Answer
D. Packet-switched
Explanation
Packet-switched networks allow communication devices in the provider network to be shared and allocated to individual subscribers during data transfer. In a packet-switched network, data is divided into small packets and sent separately across the network. These packets can take different routes to reach their destination and can be reassembled at the receiving end. This allows for efficient use of network resources and enables multiple users to share the same network infrastructure.
5.
A company needs a WAN connection that is capable of transferring voice, video, and data at a minimum data rate of 155Mbps. Which WAN connection is the best choice?
Correct Answer
C. ATM
Explanation
ATM (Asynchronous Transfer Mode) is the best choice for the company's WAN connection because it is capable of transferring voice, video, and data at a minimum data rate of 155Mbps. X.25, DSL, ISDN BRI, and ISDN PRI may not provide the required data rate or may not be suitable for transferring all three types of data effectively. Therefore, ATM is the most suitable option for the company's needs.
6.
Which two devices are commonly used as data communications equipment? (Choose two.)
Correct Answer(s)
A. Modem
C. CSU/DSU
Explanation
Modems and CSU/DSUs are commonly used as data communications equipment. Modems are used to convert digital signals into analog signals for transmission over telephone lines, allowing for communication between computers and the internet. CSU/DSUs, on the other hand, are used to connect data terminal equipment to digital transmission lines, ensuring proper signal quality and synchronization. Both devices play crucial roles in facilitating data communication and are commonly used in various networking setups.
7.
What is an advantage of packet-switched technology over circuit-switched technology?
Correct Answer
B. Packet-switched networks can efficiently use multiple routes inside a service provider network.
Explanation
Packet-switched networks have the advantage of efficiently using multiple routes inside a service provider network. This means that data packets can be sent through different paths simultaneously, increasing network efficiency and reliability. In contrast, circuit-switched networks rely on dedicated connections, which can be costly and less flexible. By utilizing multiple routes, packet-switched networks can also handle traffic congestion more effectively and provide better overall network performance.
8.
What type of connectivity is established when VPNs are used from the remote site to the private network?
Correct Answer
C. Tunnels
Explanation
When VPNs are used from the remote site to the private network, a type of connectivity known as "tunnels" is established. VPNs create secure and encrypted connections over public networks, allowing remote users to access the private network as if they were directly connected to it. These tunnels encapsulate the data packets and route them securely through the public network, ensuring privacy and data integrity.
9.
What can cause a reduction in available bandwidth on a cable broadband connection?
Correct Answer
B. Number of subscribers
Explanation
The number of subscribers can cause a reduction in available bandwidth on a cable broadband connection. When more users are connected to the same network, the available bandwidth is divided among them, resulting in a decrease in the amount of bandwidth each user can access. This can lead to slower internet speeds and reduced performance for all users on the network.
10.
What are two advantages of an analog PSTN WAN connection? (Choose two.)
Correct Answer(s)
A. Low cost
B. Availability
Explanation
An analog PSTN WAN connection offers two advantages: low cost and availability. Analog connections are generally less expensive compared to digital ones, making them a cost-effective option for businesses. Additionally, analog connections are widely available and can be easily accessed in many locations, ensuring reliable connectivity.
11.
Which packet-switched WAN technology offers high-bandwidth connectivity capable of managing data, voice, and video allon the same infrastructure?
Correct Answer
B. Metro Ethernet
Explanation
Metro Ethernet is the correct answer because it offers high-bandwidth connectivity that can handle data, voice, and video on the same infrastructure. Metro Ethernet is a type of Ethernet technology that is used in metropolitan areas to provide high-speed internet access. It is capable of supporting multiple types of traffic, including data, voice, and video, making it suitable for a wide range of applications. This technology is often used by businesses and organizations that require a reliable and high-performance network connection for their operations.
12.
Which statement is true of the functionality of the layers in the hierarchical network model?
Correct Answer
E. The distribution layer aggregates WAN connections at the edge of the campus.
Explanation
The distribution layer in the hierarchical network model is responsible for aggregating WAN connections at the edge of the campus. This layer acts as an intermediary between the access layer and the core layer, providing connectivity and routing services. It helps to manage and control the flow of network traffic within the campus network, ensuring efficient and reliable communication. By aggregating WAN connections, the distribution layer helps to optimize network performance and scalability.
13.
Which statement is true about data connectivity between a customer and a service provider?
Correct Answer
B. The segment between the demarcation point and the central office is known as the "last mile."
Explanation
The correct answer is that the segment between the demarcation point and the central office is known as the "last mile." This refers to the final stretch of connectivity between the service provider's central office and the customer's location. It is called the "last mile" because it is typically the most expensive and challenging part of the network to deploy and maintain. The CSU/DSU is the demarcation point for the service provider, not the customer. The local loop refers to the segment between the CSU/DSU and the router's serial port. The responsibility of putting data on the local loop lies with the DTE.
14.
Which statement is true about the differences between a WAN and a LAN?
Correct Answer
C. A WAN often relies on the services of carriers, such as telepHone or cable companies, but a LAN does not.
Explanation
This statement is true because WANs typically cover larger geographical areas and require the services of carriers to connect different locations. LANs, on the other hand, are usually confined to a single location and do not require external carrier services.
15.
Why is the call setup time of a circuit-switched WAN implementation considered a drawback?
Correct Answer
D. Data cannot be transferred until a circuit has been established.
Explanation
The call setup time of a circuit-switched WAN implementation is considered a drawback because data cannot be transferred until a circuit has been established. This means that there is a delay in the transmission of data as the circuit needs to be set up before any communication can take place. This can result in slower data transfer speeds and increased latency, which is a disadvantage in today's fast-paced and real-time communication requirements.
16.
For digital lines, which device is used to establish the communications link between the customer equipment and the localloop?
Correct Answer
A. CSU/DSU
Explanation
A CSU/DSU (Channel Service Unit/Data Service Unit) is a device used to establish the communications link between the customer equipment and the local loop for digital lines. It converts the digital signals from the customer equipment into a format suitable for transmission over the digital line, and vice versa. This device is commonly used in telecommunications networks to connect routers, switches, and other network devices to the digital lines provided by the service provider.
17.
A U.S. company requires a WAN connection used only to transfer sales data from individual stores to the home office. Alltransfers will occur after business hours. The required bandwidth for this connection is estimated to be less than 38 kbps.Which type of connection requires the least investment for this company?
Correct Answer
C. Analog dialup
Explanation
An analog dialup connection requires the least investment for this company because it is the most basic and inexpensive option among the given choices. Since the company only needs to transfer sales data from individual stores to the home office after business hours, a low bandwidth connection like analog dialup, which can handle data rates of up to 56 kbps, would be sufficient. ATM, ISDN, and T1 leased line connections are more advanced and expensive options that offer higher bandwidth capabilities, which are not necessary for the company's specific requirements.
18.
Which statement about WAN protocols is correct?
Correct Answer
B. Most WAN protocols use HDLC or a variant of HDLC as a framing mechanism.
Explanation
Most WAN protocols use HDLC or a variant of HDLC as a framing mechanism. This means that they use HDLC or a modified version of HDLC to encapsulate data into frames for transmission over the wide area network. HDLC is a widely used protocol that provides reliable and efficient data transmission, making it a popular choice for framing mechanisms in WAN protocols. Other WAN protocols may also use variations of HDLC to ensure the integrity and synchronization of data during transmission.
19.
Which three WAN devices can be found in the cloud? (Choose three.)
Correct Answer(s)
A. ATM switches
B. Core routers
E. Frame Relay switches
Explanation
ATM switches, core routers, and Frame Relay switches can be found in the cloud. These devices are commonly used in wide area networks (WANs) to connect multiple locations and enable communication over long distances. ATM switches are used to manage and route ATM (Asynchronous Transfer Mode) traffic, core routers are responsible for forwarding data packets between different networks, and Frame Relay switches are used to connect multiple devices in a Frame Relay network. These devices are often deployed in the cloud to provide reliable and scalable network connectivity for cloud-based applications and services.
20.
At which two layers of the OSI model does a WAN operate? (Choose two.)
Correct Answer(s)
A. pHysical Layer
B. Data Link Layer
Explanation
A WAN (Wide Area Network) operates at the Physical Layer and Data Link Layer of the OSI model. The Physical Layer is responsible for the transmission and reception of raw bit streams over a physical medium, such as cables or wireless signals. The Data Link Layer is responsible for the reliable transfer of data between network devices over a physical link, including error detection and correction. These two layers are essential for establishing and maintaining communication between devices in a WAN.