Table Of Contents
VRF-Aware H.323 and SIP for Voice Gateways
Prerequisites for VRF-Aware H.323 and SIP for Voice Gateways
Restrictions for VRF-Aware H.323 and SIP for Voice Gateways
Information About VRF-Aware H.323 and SIP
How to Configure VRF-Aware H.323 and SIP for Voice Gateways
Configuration Examples for VRF-Aware H.323 and SIP
VRF-Aware Voice Gateway: Example
Feature Information for VRF-Aware H.323 and SIP
VRF-Aware H.323 and SIP for Voice Gateways
First Published: December 22, 2006, OL-11379-01Virtual route forwarding (VRF) divides a physical router into multiple logical routers, each having its own set of interfaces and routing and forwarding tables. Adding VRF-awareness to voice gateways allows a voice gateway to exist in the same router as a customer edge (CE) or provider edge (PE) WAN router.
The VRF-Aware H.323 and SIP for Voice Gateways feature adds single voice VRF support to session-initiated protocol (SIP), H.323, and IP-to-IP gateways and to Cisco Survivable Remote Site Telephony routers.
Finding Feature Information in This Module
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 "Feature Information for VRF-Aware H.323 and SIP" section.
Finding Support Information for Platforms and Cisco IOS and Catalyst OS Software Images
Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Contents
•Prerequisites for VRF-Aware H.323 and SIP for Voice Gateways
•Restrictions for VRF-Aware H.323 and SIP for Voice Gateways
•Information About VRF-Aware H.323 and SIP
•How to Configure VRF-Aware H.323 and SIP for Voice Gateways
•Configuration Examples for VRF-Aware H.323 and SIP
•Feature Information for VRF-Aware H.323 and SIP
Prerequisites for VRF-Aware H.323 and SIP for Voice Gateways
Before you configure VRF-aware H.323 and SIP for voice gateways, you must do the following:
•Be sure that you have the correct platform to support this feature. VRF-aware H.323 and SIP is supported on the following platforms:
–For TDM-to-IP calls—Cisco 2600XM, 2691, 3700, 2800, 2801, 3800, 7200, AS5350XM, and AS5400XM
–For IP-to-IP calls— Cisco 2600XM, 2691, 3700, 2800, 2801, 3800, 7301, 7200, AS5350XM, and AS5400XM
•VRF support requires Cisco Express Forwarding switching to be enabled on the router. The above listed platforms all support Cisco Express Forwarding switching. However, customer edge (CE) or provider edge (PE) routers configured as voice gateways might require installation of additional voice interface cards and DSP modules.
Restrictions for VRF-Aware H.323 and SIP for Voice Gateways
Configuration restrictions for VRF-aware H.323 and SIP for voice gateways are as follows:
•SIP proxy and registrar must be in the same VRF.
The following call types are not supported for voice VRF:
•An IP-to-IP gateway and gatekeeper configured on the same router.
•An IP-to-IP gateway with a VRF configured on one call leg and not on another call leg.
•An IP-to-IP gateway with one VRF configured for the H.323 call leg and a different VRF configured for the SIP call leg.
•Skinny Client Control Protocol (SCCP) on Cisco SRST routers.
•SCCP on Cisco Unified Communications Manager Express (Cisco Unified CME) routers.
•SIP on Cisco Unified CME routers.
•Call that involve transcoding, including both internal and external transcoders.
•SIP calls support both TCP and UDP signaling. However, for H.323 calls, only TCP is supported. H.323 UDP signaling is not supported.
The following features are not supported by VRF-aware H.323 and SIP:
•Call-fallback and RSVP features.
•H.323 Annex E calls.
•AAA and DNS components in voice-capable access routers. These routers communicate with AAA and DNS using the default routing table.
Information About VRF-Aware H.323 and SIP
Typically, service providers use a VRF between PE and CE routers to provide VPN support for customers. VRF is also used to segment data and voice traffic for improved traffic management, and VRF can be configured on an interface to process incoming packets according to the assigned VRF.
By configuring VRF-awareness on voice gateways you can specify a VRF for the voice traffic that is generated from within the gateway. The voice VRF is added to the VoIP service provider interface (SPI) of the gateway to send and receive signaling and media packets in the configured VRF. The SPI can send signaling and media packets only in the configured VRF, and receive signaling and media packets only from the configured VRF.
How to Configure VRF-Aware H.323 and SIP for Voice Gateways
To configure a voice VRF, you must shut down voice services on the gateway, assign a previously defined VPN VRF to the VoIP SPI, and then restart voice services.
This section describes the tasks required to configure VRF-aware H.323 and SIP for voice gateways.
Note If a voice VRF is not configured, signaling and media packets are sent using the default routing table.
Prerequisites
Be sure to check the following prerequisites before configuring a voice VRF:
•To ensure there are no active calls on the voice gateway during a VRF change, you must shut down the voice gateway before you configure or make changes to a voice VRF.
•If your configuration uses address binding, use the h323-gateway voip bind srcaddr ip-address command to bind the gateway to an interface that belongs to the voice VRF.
•If the voice gateway configuration has H.323 RAS enabled, use the h323-gateway voip interface command to configure RAS on the interface that belongs to the voice VRF.
Restrictions
Restrictions for configuring VRF-aware H.323 and SIP are as follows:
•If the voice gateway configuration has H.323 RAS enabled, the gatekeeper must be accessible to the gateway in the configured voice VRF.
•When voice VRF is configured, the H.323 gateway and gatekeeper cannot communicate with each other if they are running on same router.
Voice VRF supports only the following call types:
•A single VRF for SIP-to-SIP calls
•A single VRF for H323-to-SIP calls
•A single VRF for H323-to-H323 calls
•A single VRF in IP-to-IP gateway call with a gatekeeper involved, but the gatekeeper is not on the same router.
•A SIP SRST call
SUMMARY STEPS
1. enable
2. configure terminal
3. ip vrf vrfname
4. rd route-distinguisher
5. route-target {import | export | both} route-target-ext-community
6. exit
7. voice service voip
8. shutdown
9. exit
10. voice vrf vrfname
11. voice service voip
12. no shutdown
13. end
DETAILED STEPS
Examples
!ip vrf vrf1rd 1:1route-target export 1:2route-target import 1:2!voice vrf vrf1!voice service voip!!Configuration Examples for VRF-Aware H.323 and SIP
This section provides an example configuration for a voice VRF configured on a voice gateway.
VRF-Aware Voice Gateway: Example
Router# show running configBuilding configuration...Current configuration : 1332 bytes!version 12.4service timestamps debug datetime msecservice timestamps log datetime msecno service password-encryption!hostname Router1!boot-start-markerboot-end-marker!card type e1 4 0card type t1 4 1no logging bufferedno logging console!no aaa new-model!resource policy!no network-clock-participate slot 2no network-clock-participate slot 4ip cef!ip vrf stork-vrfrd 1:1route-target export 1:2route-target import 1:2!no ip domain lookup!voice-card 0no dspfarm!voice-card 2no dspfarm!voice-card 4no dspfarm!voice vrf stork-vrf!voice service voip!controller T1 4/0framing esflinecode b8zs!controller T1 4/1shutdownframing esflinecode b8zs!controller E1 4/0/0shutdown!controller E1 4/0/1shutdown!interface GigabitEthernet0/0no ip addressno ip proxy-arpshutdownduplex autospeed automedia-type rj45negotiation auto!interface GigabitEthernet0/1no ip addressshutdownduplex autospeed automedia-type rj45negotiation auto!ip route 0.0.0.0 0.0.0.0 9.13.32.1!ip http server!control-plane!voice-port 2/0/0voice-port 2/0/1!gateway!line con 0exec-timeout 0 0stopbits 1line aux 0stopbits 1line vty 0 4login!scheduler allocate 20000 1000!endAdditional References
The following sections provide references related to VRF-Aware H.323 and SIP for Voice Gateways.
Related Documents
Related Topic Document TitleTroubleshooting VRF-aware services
IP Application Services Configuration
IP Application Services Command Reference
MPLS VPNs
MPLS Command Reference
Cisco IOS Multiprotocol Label Switching Command Reference 12.4
All other Cisco IOS Command Reference guides
Various titles located at http://www.cisco.com/en/US/customer/products/ps6350/prod_command_reference_list.html
VRF-lite
Catalyst 4500 Series Switch Cisco IOS Software Configuration Guide, 12.2(25)SG, Configuring VRF-Lite
Routers Support Resources
Information on Obtaining Documentation, Documentation Feedback, Cisco Product Security, Obtaining Technical Assistance, and Obtaining Additional Publications and Information
What's New publication, which lists all new and revised Cisco technical documentation.
Standards
MIBs
RFCs
RFC TitleNo new or modified RFCs are supported, and support for existing RFCs has not been modified.
—
Technical Assistance
Command Reference
This section documents new commands only.
New Command
voice vrf
To configure a voice VRF, use the voice vrf command in global configuration mode. To remove the voice VRF configuration, use the no form of this command.
voice vrf vrfname
no voice vrf vrfname
Syntax Description
Command Default
No voice VRF is configured.
Command Modes
Global configuration
Command History
Usage Guidelines
You must create a VRF using the ip vrf vrfname command before you can configure it as a voice VRF.
To ensure there are no active calls on the voice gateway during a VRF change, voices services must be shut down on the voice gateway before you configure or make changes to a voice VRF.
Examples
The following example shows that a VRF called vrf1 was created and then configured as a voice VRF:
ip vrf vrf1rd 1:1route-target export 1:2route-target import 1:2!voice vrf vrf1!voice service voipRelated Commands
Glossary
VRF—Virtual route forwarding.
Note See Internetworking Terms and Acronyms for terms not included in this glossary.
Feature Information for VRF-Aware H.323 and SIP
Table 1 lists the release history for this feature.
Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which Cisco IOS and Catalyst OS software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Note Table 1 lists only the Cisco IOS software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
© 2006 Cisco Systems, Inc. All rights reserved.