Cisco Cisco IOS Software Release 12.4(9)T

© 2006 Cisco Systems, Inc. All rights reserved.

The FRF .20 Support feature provides support for IP header compression (IPHC) over Frame Relay as 
described in the Frame Relay Forum Implementation Agreement FRF .20. Before the FRF .20 Support 
feature was introduced, Cisco IOS supported IPHC only on Cisco-encapsulated data-link connection 
identifiers (DLCIs) using a proprietary compression technique. This feature adds support for IPHC on 
IETF-encapsulated DLCIs.

This feature module describes how to configure FRF .20 IPHC over Frame Relay. This feature module 
also describes how to configure Enhanced Compressed Real-Time Transport Protocol (ECRTP).

Your Cisco IOS software release may not support all of the features documented in this module. To reach 
links to specific feature documentation in this module and to see a list of the releases in which each feature is 
supported, use the 

Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image 
support. Access Cisco Feature Navigator at 

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Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at 
the login dialog box and follow the instructions that appear.