Cisco Systems ASR 1000 Series

Glossary

GL-9

Cisco ASR 1000 Series Aggregation Services Routers Hardware Installation and Initial Configuration Guide

OL-13208-03

Tracing A function on the ASR 1000 Series Routers that logs internal events. Tracing cannot be disabled on the

Cisco ASR 1000 Series Router, and all tracing logs are stored in trace files.

Trace files Files that are automatically generated on the Cisco ASR 1000 Series Router that store trace data. Trace

files are usually stored automatically in a storage directory and are often useful for customer support

purposes.

UDLR Uni-Directional Link Routing

UTP Unshielded twisted pair

VAC Volts alternating current

VDC Volts direct current

VCCV Virtual Circuit Connection Verification

vDBE Virtual DBE. Represents a resource partition within a DBE. A vDBE is a type of media gateway. Each

vDBE can be controlled by a separate SBE using the H.248 protocol.

VID Vers io n I D

VRF Virtual Routing and Forwarding Instances

Virtual circuit Logical circuit created to ensure reliable communicat ion between two network devices. A virtual

circuit is defined by a VPI/VCI pair, and can be either permanent (PVC) or sw itched (SVC). Virtual

circuits are used in Frame Relay and X.25. In ATM, a virtual circuit is called a virtual channel.

VoIP Voice over Internet Protocol. The capability to carry normal telephony-style voice over an IP-based

internet with POTS-like functionality, reliability, and voice quality. VoIP enables a router to carry voice

traffic (for example, telephone calls and faxes) over an IP network. In VoIP, the DSP segments the voice

signal into frames, which then are coupled in groups of two and stored in voice packets. These voice

packets are transported using IP in compliance with ITU-T specification H.323.

VPI Virtual path identifier. 8-bit field in the header of an ATM cell. The VPI, together with the VCI,

identifies the next destination of a cell as it passes through a series of ATM switches on its way to its

destination. ATM switches use the VPI/VCI fields to identify the next VCL that a cell needs to transit

on its way to its final destination. The function of the VPI is similar to that of the DLCI in Frame Relay.

VRRP Virtual Router Redundancy Protocol