Table Of Contents
Supported Standards, MIBs, and RFCs
Configuring an H.225 TCP Timeout Value
Asociating the H.323 Voice Class with a Dial Peer
Verifying the H.225 TCP Timeout Value
Configurable Timers in H.225
Feature History
Release Modification12.1(2)T
This feature was introduced.
12.1(5)XM2
Support was added for the Cisco AS5350 and Cisco AS5400 universal gateways.
This document describes the Configurable Timers in H.225 feature, a subset of the H.323 Support for Virtual Interfaces feature that was introduced in Cisco IOS Release 12.1(2)T. This document contains the following sections:
•Supported Standards, MIBs, and RFCs
Feature Overview
The H.323 Support for Virtual Interfaces feature allows users to configure the H.225 TCP connection timeout value for all out-going call attempts (on a per VoIP dial-peer basis).
Benefits
In previous releases of the Cisco IOS software, the call attempt timeout was 15 seconds and could not be changed. In some cases, however, users might need a shorter timeout value to facilitate a faster fail-over. In other cases, users might need a greater timeout value.
The H.323 Support for Virtual Interfaces feature addresses those needs by allowing the user to override the default of 15 seconds and configure the timeout value.
Restrictions
The H.323 Support for Virtual Interfaces feature is limited to H.323 dial-peers.
Related Documents
The "Configuring VoIP" chapter of the Cisco IOS Multiservice Applications Configuration Guide
Supported Platforms
The H.323 Support for Virtual Interfaces feature is supported on any existing IOS voice platforms, including the following:
•Cisco 1700
•Cisco 2500 series
•Cisco 2600 series
•Cisco 3600 series
•Cisco 7200 series
•Cisco AS5300
•Cisco AS5350
•Cisco AS5400
•Cisco uBR900
•Cisco uBR904
•Cisco uBR910
•Cisco uBR924
•Cisco AS5400
Supported Standards, MIBs, and RFCs
Standards
No new or modified standards are supported by this feature.
MIBs
No new or modified MIBs are supported by this feature.
To obtain lists of MIBs supported by platform and Cisco IOS release and to download MIB modules, go to the Cisco MIB web site on Cisco Connection Online (CCO) at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.
RFCs
No new or modified RFCs are supported by this feature.
Prerequisites
The Cisco AS5350 and Cisco AS5400 do not support the Mica Modem Card, Microcom Modem Card, or VoIP Feature Card. Voice and modem functions are provided by the Universal Port Dial Feature card running SPE firmware. See the Cisco AS5350 Universal Gateway Card Installation Guide and the Cisco AS5400 Universal Gateway Card Installation Guide for more information. All references to the Cisco AS5300 in this document apply to the Cisco AS5350 and Cisco AS5400 platforms with the following exceptions:
•Use the Universal Port Dial Feature Card instead of the Mica or Microcom modem cards.
•Use SPE firmware instead of portware version 6.7.7.
•Run Cisco IOS Release 12.1(5)XM2 software for VoIP functionality.
Other Prerequisites
The H.323 Support for Virtual Interfaces feature requires the Cisco H.323 VoIP Gateway for Cisco Access Platforms feature.
Configuration Tasks
See the following sections for configuration tasks for the Configurable Timers in H.225 feature. Each task in the list indicates if the task is optional or required.
•Configuring an H.225 TCP Timeout Value (required)
•Asociating the H.323 Voice Class with a Dial Peer (required)
•Verifying the H.225 TCP Timeout Value (optional)
Configuring an H.225 TCP Timeout Value
To use the H.323 Support for Virtual Interfaces feature, you must first create an H.323 voice class and then specify the timeout value associated with that class. To configure the H.225 TCP timeout value, do the following:
Asociating the H.323 Voice Class with a Dial Peer
Next, you must associate the H.323 voice class with each VoIP dial peer that should use the specified timeout. To associate the H.323 voice class with a dial peer, do the following:
Verifying the H.225 TCP Timeout Value
To verify the timeout value are defined for a dial peer, enter the show run command. The output shows the current configuration of the voice class and the dial peer.
router# show runBuilding configuration...Current configuration:!...voice class h323 1h225 timeout tcp etablish 10dial-peer voice 919 voipapplication sessiondestination-pattern 919555....voice-class codec 1voice-class h323 1session target ras...Configuration Examples
In the following example,a timeout value of 10 is configured for the H.323 voice class labled 3. Voice class 3 is then associated with the dial-peer identified as 919. This sets the H.225 TCP timeout for dial-peer 919 to 10.
voice class h323 1h225 timeout tcp etablish <value 0 to 30 seconds>dial-peer voice 919 voipapplication sessiondestination-pattern 919555....voice-class codec 1voice-class h323 1session target rasCommand Reference
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.1 command reference publications.
h225 timeout tcp establish
To set the H.225 TCP timeout value for VoIP dial peers, use the h225 timeout tcp establish subcommand. To set the timeout back to its default, use the no form of the command.
h225 timeout tcp establish value
no h225 timeout tcp establish
Syntax Description
value
Specify the number of seconds for the timeout. Possible values are 0 to 30. The default is 15. If you specify 0, the H.225 TCP timer is disabled.
Defaults
The default is 15 seconds.
Command Modes
Voice class configuration
Command History
Release Modification12.1(2)T
This command was introduced.
12.1(5)XM2
The command was introduced for the Cisco AS5350 and CiscoAS5400.
Usage Guidelines
None
Examples
The following example configures a timeout of 10 seconds, which is associated with the H.323 voice class labeled 1:
voice class h323 1h225 timeout tcp establish 10Related Commands
voice class h323
To create an H.323 voice class that is independent of a dial peer and can be used on multiple dial peers, use the voice class h323 command. To remove the voice class, use the no form of the command.
voice class h323 number
no voice class h323
Syntax Description
Defaults
There are no default behaviors or values for this command.
Command Modes
Global configuration
Command History
Release Modification12.1(2)T
This command was introduced.
12.1(5)XM2
The command was introduced for the Cisco AS5350 and CiscoAS5400.
Usage Guidelines
None
Examples
The following example creates an H.323 voice class labeled 1:
voice class h323 1Related Commands
Glossary
gatekeeper—A gatekeeper maintains a registry of devices in the multimedia network. The devices register with the gatekeeper at startup, and request admission to a call from the gatekeeper.
The gatekeeper is an H.323 entity on the LAN that provides address translation and control access to the LAN for H.323 terminals and gateways. The gatekeeper may provide other services to the H.323 terminals and gateways, such as bandwidth management and locating gateways.
gateway—A gateway allows H.323 terminals to communicate with non-H.323 terminals by converting protocols. A gateway is the point at which a circuit-switched call is encoded and repackaged into IP packets.
A H.323 gateway is an endpoint on the LAN that provides real-time, two-way communications between H.323 terminals on the LAN and other ITU-T terminals in the WAN, or to another H.323 gateway.
H.323—An International Telecommunication Union (ITU-T) standard that describes packet-based video, audio, and data conferencing. H.323 is an umbrella standard that describes the architecture of the conferencing system, and refers to a set of other standards (H.245, H.225.0, and Q.931) to describe its actual protocol.
RAS—Registration, admission, and status protocol. This is the protocol that is used between endpoints and the gatekeeper to perform management functions. The RAS signaling function performs registration, admissions, bandwidth changes, status, and disengage procedures between the VoIP gateway and the gatekeeper.
RTP—Real-time transport protocol. One of the IPv6 protocols. RTP is designed to provide end-to-end network transport functions for applications transmitting real-time data, such as audio, video, or simulation data, over multicast or unicast network services. RTP provides services such as payload type identification, sequence numbering, timestamping, and delivery monitoring to real-time applications.
VoIP—Voice over IP. The ability to carry normal telephone-style voice over an IP-based Internet with POTS-like functionality, reliability, and voice quality. VoIP is a blanket term which generally refers to Cisco's standards-based (H.323, etc.) approach to IP voice traffic.
Note For a list of other internetworking terms, see Internetworking Terms and Acronyms, available on the Documentation CD-ROM and Cisco Connection Online (CCO) at the following URL: http://www.cisco.com/univercd/cc/td/doc/cisintwk/ita/index.htm.