Mark works as a Network Administrator for NetTech Inc. He wants to connect the company's headquarter and its regional offices using a WAN technology. For this, he uses packet-switched connection.
Which of the following WAN technologies will Mark use to connect the offices? Each correct answer represents a complete solution. Choose two.
- ISDN
- X.25
- Frame Relay
- Leased line
Answer(s): B,C
Explanation:
According to the question, Mark will use X.25 or Frame Relay WAN connection for connecting the headquarter and regional offices. Frame Relay and X.25 are packet-switched connections.
A packet-switched connection is a type of network in which packets, which are small units of data, are routed through a network. The communication is based on the destination address contained within each packet. Packet-switched connections are logical circuits to make connection between two sites. These logical circuits are also called virtual circuits. A virtual circuit is not tied to any physical circuit, and therefore it is possible to make multiple logical circuits on a single physical circuit. Frame relay and X.25 are examples of packet-switched networks.
Answer option A is incorrect. ISDN is a type of circuit switched-connection. A circuit-switched connection is a type of network in which a physical circuit is established between two end-points for the duration of the connection. During this time, none else can use the physical lines involved. Circuit-switched connections are dial-up connections that include two types of connections: asynchronous and synchronous serial connections. Plain old telephone system (POTS) uses asynchronous serial connections, whereas ISDN uses synchronous serial connections. Answer option D is incorrect. Leased line is not a type of packet-switched connection. Leased lines are used for short distance connection and when you have a constant amount of traffic on the connection with a requirement of guaranteed bandwidth.