Wireless Mobile Communications — Test 4

Correct Answer: C. C. Access signalling
Explanation: Access signalling supports traffic between the end user and the network. It defines how end users obtain access to the PSTN and the ISDN for communication or services.

Correct Answer: B. B. False
Explanation: The second signalling component of ISDN, network signalling is governed by the SS7 suite of protocols. For wireless communication systems, the SS7 protocols within ISDN are critical to providing backbone network connectivity between MSCs throughout the world.

Correct Answer: C. C. B channels
Explanation: The ISDN interface is divided into three different types of channels. Information bearing channels called bearer channels (B channels) are used exclusively for end user traffic (voice, data and video).

Correct Answer: B. B. False
Explanation: ISDN provides integrated end-user access to both circuit switched and packet switched networks with digital end-to-end connectivity.

Correct Answer: B. B. False
Explanation: ISDN end users may select between two different interfaces. The BRI (basic rate interface) is intended to serve small capacity terminals while the PRI (primary rate interface) is intended for large capacity terminals.

Correct Answer: D. D. B-isdn
Explanation: Emerging networking technique, broadband ISDN (B-ISDN) is based on asynchronous transfer mode (ATM) technology. It allows packet switching rates up to 2.4 Gbps and total switching capacities as high as 100 Gbps.

Correct Answer: C. C. Multiplexing technique
Explanation: ATM is a packet switching and multiplexing technique which has been specifically designed to handle both voice users and packet data users in a single physical channel.

Correct Answer: B. B. False
Explanation: ATM supports bidirectional transfer of data packets of fixed length between two end points. It preserves the order of transmission.

Correct Answer: A. A. Cell
Explanation: The data unit of ATM is cell. They are routed based on header information in each unit (called a label) that identifies the cell as belonging to a specific ATM virtual connection.

Correct Answer: D. D. 53 bytes
Explanation: ATM cells have a fixed length of 53 bytes. It consists of 48 bytes of data and 5 bytes of header information. Fixed length packets result in simple implementation of fast packet switches.