Avaya M770 ATM Switch User’s Guide 293

Appendix D

Creating PVPs
This appendix describes the procedure for creating PVPs on Avaya M770 ATM
Modules.

Creating PVPs

What do you do when you want all VCs from a particular VPI to be switched from
one endpoint to another? You would define a Permanent Virtual Path (PVP). When
a PVP is configured, the cell is switched using only its VPI - the VCI is ignored. The
VPI on the ingress port can be the same or different than the VPI on the egress port.
This section contains examples on defining PVPs. The following 2 examples show
in detail how to define PVPs between ports on the same module and between ports
on different modules in the ATM switch.
Example 1
Define a PVP that takes all VCs coming in on slot 1 port 1 for VPI 6 and switch them
to slot 1 port 2 VPI 7.
Example 2
Define a PVP that takes all VCs coming in on slot 1 port 1 for VPI 6 and switch them
to slot 3 port 2 VPI 7.
There are four steps in creating a PVP on the M770 ATM switch:
1 Define the VPI range that is used for VP switching
2 Define the VPI range to be used for Signalled VPs. The rest are used for
Permanent VPs
3 Create the Traffic Descriptor (TD) that will be used for the PVP
4 Create the PVP.
Before you get started, there is an additional command/feature in the M770 ATM
switch to help you configure PVPs. This is the ability to change the maximum
number of VPIs on the module. For example, the default configuration for the M15-
155 is 3 bits for the VPI range and 12 bits for the VCI range. This gives you a total of
8 VPIs (23) to play with. If more VPIs are needed, you can “steal” them from the
VCI range. By using the command hardware vpivcirange, you can allocate up to 6
bits for the VPI range (26 or 64 VPIs). For more information on changing the VPI
and VCI bit range, please see section "“Managing the number of VPI and VCI bits”
on page 98.
For our examples, it is assumed that the module is an M15-155 and its VPI and VCI
bits are set to 3 and 12 accordingly.