| |
The source route bridge treats NetWare Link/Frame Relay as a switched virtual circuit (SVC) rather than a PVC. The bridge uses a Call Target Name to connect to a particular target, as in NetWare Link/X.25 or NetWare Link/PPP. Bridging does not need to be configured on every router that is connected to the frame relay switch across the frame relay network. You must bind to each target (DLCI) independently, regardless of the number of DLCIs configured at that site. Use NIASCFG to enter DLCIs for configuring a WAN call destination. This process is similar to adding a DTE address in X.25 configurations.
When you bind the bridge to a DLCI, the bridge logic binds and posts a listen on that NetWare Link/Frame Relay interface. To inform the bridge about the availability of all the DLCIs that are configured for that interface, NetWare Link/Frame Relay calls the bridge with multiple incoming calls. The bridge accepts all the DLCIs and saves them in a table.
However, the bridge establishes a link only with the DLCI that has been configured by the user. The next time, if there is another bind to a different DLCI, and if the bridge already has that DLCI in its table, it brings up the link; otherwise, the bridge retains the bind for that DLCI and waits until that DLCI is given as an incoming call by the NetWare Link/Frame Relay logic.
Therefore, even though the bridge accepts all the DLCIs given by NetWare Link/Frame Relay from a bridge/spanning tree perspective, only the links whose DLCIs are configured through the Call Target configuration in NIASCFG are brought up. Each DLCI connection is treated as a separate bridge port; any loops inside the frame relay network are detected, and the appropriate bridge port is blocked. This method also lets you configure various source routing parameters, such as ring number, to be configured on a per-bridge port basis. Make sure you configure the right combination of DLCIs and ring numbers on the frame relay links.
You can configure concurrent bridging and routing on the same DLCI. When you do this, routing is done for one protocol, and bridging handles the rest of the protocols that are not configured for routing.
IMPORTANT: If you define more than one PVC between two routers for bridging, you cannot use the VWR=NO option. When binding a source route bridge to a NetWare Link/Frame Relay interface, you must select the VWR=YES option on all PVCs that are defined between the two routers.
| |