Configuring Cisco CallManager for Video

When you are setting up a video IP telephony environment, you first have to configure video in Cisco CallManager. Cisco VT Advantage requires Cisco CallManager to handle video call processing. Before enabling video on Cisco CallManager, you must update your locations and regions settings to adjust your bandwidth settings. Media Resource Group Lists (MRGLs) are used to control the access to multipoint control units (MCUs). Only devices that are allowed to use an MRGL are able to use the resources in the MRGL. Using this feature, you should restrict access to the video conference MCU resources to only the video-capable endpoints. Otherwise, the MCU resources could be depleted by managing audio conferences best handled by other hardware.

Further, you have to reconsider the call-routing configuration when using, for example, Automated Alternate Routing (AAR). Another important point that arises during the consideration of video is the Differentiated Services Code Point (DSCP) settings for quality of service (QoS).

In large Cisco CallManager environments, you have to consider whether it makes sense to use the Cisco VT Advantage Deployment Tool to make Cisco VT Advantage software available for download in Cisco CallManager.

Call-Routing Considerations

One of the advantages of using Cisco VT Advantage is that you can use the existing dial plan. If the bandwidth needed by an endpoint for a video call is not available, by default the call is retried as an audio call. To use route or hunt lists or AAR groups to try different paths for such video calls instead of retrying them as audio calls, uncheck the Retry Video Call as Audio check box in the configuration settings for the applicable gateways, trunks, and IP phones.

Video-enabled IP phones should have a separate MRGL with the videoconference bridge as the first choice. If the nonvideo-enabled IP phones use the videoconference bridge as a first choice, you run the risk of having no videoconference resources available for videoconference calls because all the videoconference resources are occupied by audio-only conferences. It is recommended that you create two separate MRGLsone for video-enabled IP phones and one for nonvideo-enabled IP phones.

Video is as time-critical as voice. In a voice- and video-enabled network, you have to prioritize voice and video packets so that you do not experience quality issues. Both voice and video must be of higher priority than data, for example.

DSCP packet marking includes these characteristics:

• Audio streams in audio-only calls default to the Expedited Forwarding (EF) class.
• Video streams and associated audio streams in video calls default to Assured Forwarding, Class 4, with low drop precedence (AF41).

You can change these defaults using the Cisco CallManager Enterprise Parameters.

These service parameters affect DSCP packet marking:

• DSCP for Audio Calls (for Media RTP Streams) This parameter specifies the DSCP value for audio calls.
• DSCP for Video Calls (for Media RTP Streams) :This parameter specifies the DSCP value for video calls.

VT Advantage Deployment Tool

For simplified and scalable deployment of Cisco VT Advantage client installation software, you can use the Cisco VT Advantage Deployment Tool. Administrators can use this tool to make the Cisco VT Advantage installer program available on a Cisco CallManager publisher server. The installer program will then reside in the CCMPluginsClient website that is mapped to the C:CiscoPluginsClientCVTA directory. This website is set up with the correct permissions to allow anonymous access to the Cisco VT Advantage Installer executable file to facilitate installation for your technicians and users.

The Cisco VT Advantage Deployment Tool lets you set these options for the installation:

• AutoUpdate Sets the AutoUpdate option so that users are notified automatically about updates to Cisco VT Advantage
• Proxy Sets proxy server information for users needing to use a proxy server to reach the Cisco CallManager publisher server
• Error Reporting Tool Sets the e-mail or FTP addresses where users send reports generated by the Error Reporting Tool

To publish Cisco VT Advantage to Cisco CallManager, the administrator must download the latest available Cisco VT Advantage Deployment Tool from Cisco.com. Run the DeployMan.exe file to set up Cisco VT Advantage for end users. The Cisco VT Advantage installer program is now stored in Cisco CallManager and a download link will be made available on Cisco CallManager user-accessible installation pages.

To install Cisco VT Advantage on a PC, users must complete these steps:

Step 1.	Access the Cisco CallManager user installation page and download the Cisco VT Advantage software: https:///CCMUser. (This URL is found in the Services Help screen on Cisco IP Phone models that support Cisco VT Advantage.)
Step 2.	Install Cisco VT Advantage software on the PC.

When you execute the DeployMan.exe file, the DeployMan window opens, as shown in Figure 29-2. When you click the Use Defaults button in the DeployMan main window, the Cisco VT Advantage Deployment Tool must be running on the Cisco CallManager publisher server. If this is not the case, change the path in the CVTAInstall.exe Destination field by referring to the C:CiscoPluginsClientCVTA directory at the publisher via a network file share. The Choose Host Name dialog box opens. Enter the hostname (or IP address) of the Cisco CallManager publisher server. This value populates the Update URL field for the AutoUpdate feature.

Figure 29-2. Using the VT Advantage Deployment Tool

These fields are automatically populated with default values:

• Cisco VT Advantage Version
• CVTAInstall.exe Destination
• Update URL
• Comma-Delimited E-Mail/FTP Addresses

Make sure that the Update URL field in the AutoUpdate Options area contains the hostname (or IP address) of the Cisco CallManager publisher server. If you do not want to use AutoUpdate, uncheck the Deploy AutoUpdate check box. The Precertification Options area will be usable only in later versions of the deployment tool, even though it is shown in the GUI of the current version (2.0).

If users in the network need to use a proxy server to reach the Cisco CallManager publisher server, check the Use HTTP Proxy check box and fill in the Proxy URL and Proxy Port fields with the appropriate values.

In the Comma-Delimited E-Mail/FTP Addresses field of the Error Reporting Tool Options, enter the e-mail or FTP addresses to which error reports generated by users can be sent. You can enter multiple addresses separated by commas. The default e-mail address is [e-mail]. This e-mail address is used by the Cisco Technical Assistance Center (TAC) to pick up files sent by customers.

When you have filled in all necessary options, click OK to make the Cisco VT Advantage installation program available to users.

Configuring Cisco IP Phones for Cisco VT Advantage