IBM SG24-4817-00 Switch User Manual


 
This soft copy for use by IBM employees only.
The maximum number of VPI connections supported per 25 Mbps port is 16
and 64 for the others.
5.1.4 How PVCs Are Supported
To support PVCs, the 8285 maps them internally onto SVCs. This allows the PVC
to be automatically reestablished using an alternate path in case of a link or
node failure on the original path supporting the PVC. In addition, the parameters
specified for the setting of the PVCs are saved in the NVRAM of the 8285 to
provide automatic reestablishment of the PVC after the 8285 power off or reset
condition.
Note that the information about PVCs is only stored in NVRAM after the
connection is activated. This is to ensure that only the current and valid PVCs
are restarted.
When an 8285 is restarted and an SVC is to be established before all the PVCs
have been reestablished, a problem could occur if that SVC is allocated a label
that is owned by one of the PVCs. To overcome this problem, the 8285 always
checks to see if a label is not reserved by a PVC before allocating it to an SVC.
5.1.5 How to Configure PVCs
PVCs can be set up using the command line interface or the Nways Campus
manager program. The following example shows how to configure a PVC for the
configuration shown in Figure 32.
Figure 32. Sample PVC Configuration
Chapter 5. 8285 ATM Network Specifications 83