Panasonic 1200N manual Vpi, Vpl, Vpt, Vs/Vd, Wan

Glossary W

VPI

Virtual Path Identifier: An eight bit field in the ATM cell header which indicates the virtual path over which the cell should be routed.

VPL

Virtual Path Link: A means of unidirectional transport of ATM cells between the point where a VPI value is assigned and the point where that value is translated or removed.

VPT

Virtual Path Terminator: A system that unbundles the VCS of a VP for independent processing of each VC.

VS

Virtual Scheduling: Virtual Scheduling is a method to determine the conformance of an arriving cell. The virtual scheduling algorithm updates a Theoretical Arrival Time (TAT), which is the "nominal" arrival time of the cell assuming that the active source sends equally spaced cells. If the actual arrival time of a cell is not "too" early relative to the TAT, then the cell is conforming. Otherwise the cell is non- conforming.

VS

Virtual Source. Refer to VS/VD.

VS/VD

Virtual Source/Virtual Destination: An ABR connection may be divided into two or more separately controlled ABR segments. Each ABR control segment, except the first, is sourced by a virtual source. A virtual source implements the behavior of an ABR source endpoint. Backwards RM-cells received by a virtual source are removed from the connection. Each ABR control segment, except the last, is terminated by a virtual destination. A virtual destination assumes the behavior of an ABR destination endpoint. Forward RM-cells received by a virtual destination are turned around and not forwarded to the next segment of the connection.

W

WAN

Wide Area Network: A network which spans a large geographic area relative to office and campus environment of LAN (Local Area Network). WAN is characterized by having much greater transfer delays due to laws of physics.

Centillion 1200N ATM Switch User Manual	B-85
NTP 297-8103-903