| A | B |
|---|
| circuit | Communications path between two or more points. |
| circuit switching | system in which a dedicated physical circuit path must exist between sender and receiver for the duration of the "call." Used heavily in the telephone company network |
| enterprise network | Large and diverse network connecting most major points in a company or other organization. Differs from a WAN in that it is privately owned and maintained |
| Frame Relay | Industry-standard, switched data link layer protocol that handles multiple virtual circuits using HDLC encapsulation between connected devices |
| leased line | Transmission line reserved by a communications carrier for the private use of a customer |
| link | Network communications channel consisting of a circuit or transmission path and all related equipment between a sender and a receiver. Most often used to refer to a WAN connection |
| packet switching | Networking method in which nodes share bandwidth with each other by sending packets. |
| packet switch | WAN device that routes packets along the most efficient path and allows a communications channel to be shared by multiple connections. |
| T1 | Digital WAN carrier facility; transmits DS-1-formatted data at 1.544 Mbps through the telephone-switching network, using AMI or B8ZS coding |
| T3 | Digital WAN carrier facility; transmits DS-3-formatted data at 44.736 Mbps through the telephone switching network. |
| circuit-switched networks offer users dedicated bandwidth that cannot be | infringed upon by other users. |
| packet switching is a method in which network devices share a | single point-to-point link to transport packets from a source to a destination across a carrier network. |
| Packet-switched networks have traditionally offered more flexibility and used network bandwidth | more efficiently than circuit-switched networks. |
| WAN communication characteristics | relatively low throughput, high delay, and high error rates |
| Network usage has increased as enterprises utilize | client/server, multimedia, and other applications to enhance productivity. |
| The explosive growth of corporate intranets and extranets has created a | greater demand for bandwidth. |
| WAN connections generally handle important information and are optimized for | price and performance bandwidth. |
| . In the WAN, _________ is the overriding cost, | bandwidth |
| Two primary goals drive WAN design and implementation: | Application availability, total cost of ownership |
| WAN design needs to take into account these general factors | Environmental variables, performance constraints, networking variables |
| Environmental variables include | the location of hosts, servers, terminals, and other end nodes; the projected traffic for the environment; and the projected costs for delivering different service levels |
| Performance constraints consist of | network reliability, traffic throughput, and host/client computer speeds |
| Networking variables include the | network topology, line capacities, and packet traffic. |
| The overall goal of WAN design is to minimize cost based on these elements while delivering service that does not compromise established availability requirements. | minimize cost while delivering service that does not compromise established availability requirements. |
| The first step in the design process is to | understand the business requirements |
| The chief components of application availability are | response time, throughput, and reliability |
| Response time is the time between | entry of a command or keystroke and the host system's execution of the command or delivery of a response. |
| Throughput-intensive applications generally involve | file-transfer activities. |
| You can assess user requirements by | User community profiles, Interviews, focus groups, and surveys ,conduct interviews with key user groups, and human factors tests |
| The objective of analyzing requirements is to determine, | the average and peak data rates for each source over time |
