Octal-Port DMT ATU-C Line Card
Glossary
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Cisco IOS Release 12.1(6)DA
U
upstream rate
The line rate for message or data transfer from the source machine to a destination machine on the
network. Also see downstream rate.
V
VC
Virtual circuit. A logical circuit created to ensure reliable communication between two network
devices. A virtual circuit is defined by a VPI/VCI pair, and can be either permanent (PVC) or switched
(SVC). In ATM, a virtual circuit is called a virtual channel. Sometimes abbreviated VC. See also PVC,
SVC, VCI, and VPI.
virtual circuit
See VC.
VCI
Virtual channel identifier. A 16-bit field in the header of an ATM cell. The VCI, together with the VPI,
is used to identify the next destination of a cell as it passes through to the ATM switch. Sometimes
called virtual channel connection. See also VPI.
VPI
Virtual path identifier. An 8-bit field in the header of an ATM cell. The VPI, together with the VCI, is
used to identify the next destination of a cell as it passes through the network. See also VCI.
