3Com 7000 manual Glossary

140GLOSSARY

ATM Forum UNI documents. The standard adopted by the ATM Forum to define connections between users or end stations and a local switch.

V

VBR Variable Bit Rate. An ATM Forum defined service category which supports variable bit rate data traffic with average and peak traffic parameters.

VC Virtual Channel. A communication channel that provides for the sequential unidirectional transport of ATM cells.

VCC Virtual Channel Connection. A concatenation of virtual channel links that extends between the points where the ATM service users access the ATM layer. The points at which the ATM cell payload is passed to, or received from, the users of the ATM layer for processing signify the endpoints of a VCC. VCCs are unidirectional.

VCI Virtual Channel Identifier. Part of the identifier of a particular virtual circuit in the ATM fabric.

VP Virtual Path. A unidirectional logical association or bundle of VCs.

VP Tunneling Virtual Path Tunneling. A virtual path which has been extended to include a signaling channel and an ILMI channel in addition to the call channels.

VPI Virtual Path Identifier. Part of the identifier of a particular virtual circuit in the ATM fabric.

W

WAN Wide Area Network. Data communications network spanning very large geographical areas.