Configuring Frame Relay Stac Compression; Configuration Restrictions And Guidelines; Configuring Frame Relay Stac Compression On A Virtual Circuit; Configuring Frame Relay Frf.12 Fragmentation - HP MSR Router Series Wan Access Configuration Manual

Configuring Frame Relay STAC compression

STAC compression is a payload compression method that applies to Frame Relay packets and InARP
packets. STAC compression cannot compress LMI messages.
The two ends of a PVC negotiate the PVC state by using STAC control messages after STAC compression
is enabled. The PVC state negotiation succeeds only when STAC compression is enabled on both ends
of the PVC. After PVC state negotiation succeeds, both ends can transmit compressed packets on the PVC.
If one end does not receive response messages from the peer after sending 10 control messages, it stops
sending control messages. The PVC state negotiation fails.

Configuration restrictions and guidelines

When you configure Frame Relay STAC compression, follow these restrictions and guidelines:
• To make STAC compression take effect on a PVC, you must enable Frame Relay STAC compression
on both ends of the PVC.
STAC compression works only when the encapsulation type is IETF on both ends of a PVC. If the
•
encapsulation type is not IETF when you enable STAC compression, the system automatically
changes the encapsulation type to IETF.
Frame Relay IPHC and STAC compression are mutually exclusive.
•

Configuring Frame Relay STAC compression on a virtual circuit

Step
1. Enter system view.
2. Enter interface view.
3. Create a virtual circuit on the
interface.
4. Enable STAC compression on
the virtual circuit.

Configuring Frame Relay FRF.12 fragmentation

FRF.12 fragmentation divides large packets into smaller fragments at the sending end and reassembles
the fragments at the receiving end. This process helps reduce the transmission delay for realtime traffic
when realtime traffic and non-realtime traffic are transmitted together on low-speed links. FRF.12
fragmentation takes effect only on outgoing packets.
FRF.12 fragmentation includes the following types:
NNI&UNI.
•
End-to-end.
•
Only end-to-end FRF.12 fragmentation is supported in the current software version.
Command
system-view
interface interface-type
interface-number
fr dlci dlci-number
fr compression stac enable
242
Remarks
N/A
The interface can be a main
interface or a subinterface.
By default, no virtual circuits exist
on an interface.
By default, STAC compression is
disabled on a virtual circuit.