Cisco Cisco IOS Software Release 12.2(27)SBC

Copyright © 2006 Cisco Systems, Inc. All rights reserved.

This module explains how to ensure that virtual private network (VPN) clients that connect to the same 
provider edge (PE) router at the edge of the Multiprotocol (MPLS) Virtual Private Network (VPN) use 
the hub site. This feature prevents the VPN clients from communicating directly with each other by 
bypassing the hub site. This feature also provides scalable hub-and-spoke connectivity for subscribers 
of an MPLS VPN service by removing the requirement of one VRF per spoke. 

This module was first published on May 2, 2005, and was most recently updated on May 23, 2006.

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MPLS VPN: Half Duplex VRF 
Support

12.3(6)

12.3(11)T 

This feature ensures that VPN clients that connect to 
the same PE router at the edge of the MPLS VPN use 
the hub site to communicate. 

Configuring Scalable 
Hub-and-Spoke MPLS VPNs

12.2(28)SB

The feature was integrated into the SB train.

MPLS VPN Half-Duplex VRF

12.2(28)SB2

Support for dynamic routing protocols was added. 

For the Cisco 10000 series routers, see the 
“Half-Duplex VRF” section of the “Configuring 
Multiprotocol Label Switching” chapter in the 

at the 

following URL: