NT1210
Cynthia Allen
Unit 7
Chapter Review Questions

Key Terms
1. Switched Circuits – A circuit created by the phone company in reaction to signaling ( the user tapping telephone keys or modem sending the same digits w/ the Telco tearing down the circuit when the user is finished.
2. Dedicated circuit – A electrical circuit created by a telco CO. on behalf of a customer, with circuits staying up all the time, dedicated for use by the customer that ordered the circuit, also known as leased lines, leased circuit and point to point.
3. Circuit switching - The overall process by which a series of Telco devices called circuit switches connect a circuit from one customer to another, with the device taking bits on one segment in the link and forwards those bits out the matching outgoing segment without storing the bits.
4. Leased line – A physical link between two locations provided by Telco, that allows two way communications between sites. Because the customer does not own the physical line between the sites, but rather pays a monthly fee for service called a leased line “AKA” dedicated circuit, leased circuit, and point-to-point.
5. Packet switching – The process of forwarding customers data in a WAN by looking at the header of the header of the message sent into the WAN by the customer and making a peer message (per-packet) decision as to where to forward each message.
6. Time –division- multiplexing –A type of logic used by some networking devices including switches in the Telco, in which the switch devices a faster speed line into time channel. The TDZ logic takes the bits of the slower speed lines and forward those bits inside channel in high speed line (multiplexing) and receiving bits on higher – speed lines, finds the bits in each time channel and spits those back out to the slower speed lines called DE multiplexing.
7. T-Carrier System – The