20-40
ATM Switch Router Software Configuration Guide
OL-7396-01
Chapter 20
Configuring Frame Relay to ATM Interworking Port Adapter Interfaces
Configuring Frame Relay to ATM Virtual Connections
Standard Signalling for Frame Relay Soft PVCs
Standards-based signalling for Frame-Relay Soft PVCs requires using new fields in the calling and
called Soft PVC Information Elements (IEs) to convey the local and remote Data Link Control Identifiers
(DLCI). The default proprietary signalling also transmits the intended Discard Eligibility (DE) and Cell
Loss Priority (CLP) -bit handling for the connection. This cannot be signalled if standard signalling is
configured. To use standard signalling for soft PVCs, you can configure the Frame Relay interface to
specify the default CLP or DE mapping for received soft PVC connections.
To set the default mode for received soft PVC connections in the Frame Relay to ATM direction, use the
following interface command:
Note
Values 0, 1, or
map-de
are allowed for both network interworking and service interworking. The default
is
map-d
e.
To set the default mode for received soft PVC connections in the ATM to Frame Relay direction, use the
following interface command:
Note
For network interworking, values
map-de
or
map-clp-or-de
are allowed. The default value is
map-clp-or-d
e. For service interworking, values 0, 1, or
map-clp
are allowed. The default is
map-cl
p.
Configuring the Soft PVC Route Optimization Feature
This section describes the soft permanent virtual channel (soft PVC) route optimization feature for
Frame Relay interfaces. Most soft PVCs have a much longer lifetime than switched virtual channels
(SVCs). The route chosen during the soft connection setup remains the same even though the network
topology might change.
Soft connections, with the route optimization percentage threshold set, provide the following features:
•
When a better route is available, soft permanent virtual paths (soft PVPs) or soft PVCs are
dynamically rerouted.
•
Route optimization can be triggered manually.
Command
Purpose
Switch(config-if)#
frame-relay called-soft-vc
default clp-bit
[
0 | 1 | map-de
]
Sets the default mode for received soft PVC
connections in the Frame Relay to ATM
direction, including the mode of DE/CLP
mapping.
Command
Purpose
Switch(config-if)#
frame-relay called-soft-vc
default de-bit
[
map-clp-or-de | map-de
]]
Sets the default mode for received soft PVC
connections in the ATM to Frame Relay
direction, including the mode of DE/CLP
mapping.