Wireless Mobile Communications — Test 2

Correct Answer: D. D. Four
Explanation: Four levels of addresses are used in the internet employing the TCP/IP protocols. They are physical (link) addresses, logical (IP) addresses, port addresses, and specific addresses.

Correct Answer: B. B. Application layer
Explanation: In open systems, a virtual terminal (VT) is an application service. It allows host terminals on a multi-user network to interact with other hosts regardless of terminal type and characteristics.

Correct Answer: A. A. Arpanet
Explanation: In 1983, TCP/IP protocols replaced NCP (Network Control Program) as the ARPANET’s principal protocol. And ARPANET then became one component of the early Internet. The starting point for host-to-host communication on the ARPANET in 1969 was the 1822 protocol, which defined the transmission of messages to an IMP.

Correct Answer: A. A. Router
Explanation: A router is a networking device that forwards data packets between computer networks. Routers perform the traffic directing functions on the Internet. It supports different network layer transmission standards. Each network interface is used to enable data packets to be forwarded from one transmission system to another.

Correct Answer: D. D. Repeater
Explanation: A repeater connects two segments of your network cable. It retimes and regenerates the signals to proper amplitudes and sends them to the other segments. Repeaters work only at the physical layer of the OSI network model.

Correct Answer: D. D. L2cap
Explanation: L2CAP is Logical Link, Control Adaptation Protocol Layer. The logical unit link control adaptation protocol is equivalent to logical link control sub layer of LAN. The ACL link uses L2CAP for data exchange. The various function of L2CAP is segmentation and reassembly, multiplexing and quality of service.

Correct Answer: A. A. Communication
Explanation: A protocol is a set of rules that governs the communications between computers on a network. These rules include guidelines that regulate the characteristics of a network including access method, allowed physical topologies, types of cabling, and speed of data transfer.

Correct Answer: B. B. Network of networks
Explanation: Internet is a massive network of networks, a networking infrastructure. It connects millions of computers together globally, forming a network in which any computer can communicate with any other computer as long as they are both connected to the Internet.

Correct Answer: D. D. Data link layer
Explanation: The checksum is used in the Internet by several protocols although not at the data link layer. Like linear and cyclic codes, the checksum is based on the concept of redundancy. Several protocols still use the checksum for error detection.

Correct Answer: A. A. Discarded
Explanation: A 4 bit field defines the version of IPv4 protocol. This field tells the software running in the processing machine that the datagram has the format of version 4. If the machine is using some other version of IPv4, the datagram is discarded rather than interpreted incorrectly.