Cisco Systems ASR 1000 Series manual GL-9

Tracing

Trace files

Glossary

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.

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.

U

UDLR	Uni-Directional Link Routing
UTP	Unshielded twisted pair

V

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		Version ID
VRF		Virtual Routing and Forwarding Instances
Virtual circuit		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). 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
W
		Cisco ASR 1000 Series Aggregation Services Routers Hardware Installation and Initial Configuration Guide
	OL-13208-03		GL-9