Introduction to Media Resources

A media resource is a software-based or hardware-based entity that performs media processing functions on the voice streams to which it is connected. Media-processing functions include mixing multiple streams to create mixed, unicast output streams (conferencing), passing the stream from one connection to another (Media Termination Point), converting the data stream from one compression type to another (transcoding), streaming voice progress tones (annunciation), and music on hold.

Every Cisco CallManager contains a software component called a Media Resource Manager (MRM) that communicates with MRMs on other Cisco CallManager servers. The MRM locates a media resource to connect the media streams and to complete the feature. The MRM manages the following media resource types:

• Conference bridge
• MTP
• Annunciator
• Transcoder
• MoH server

Note

To act as a Media Resource Manager, you must activate the Voice Media Streaming Application service on the Cisco CallManager server. This service is discussed in detail later in this chapter.

Your Cisco CallManager servers can also participate in the media-processing functions in the cluster. After Cisco CallManager is installed, you must activate these two Cisco CallManager services:

• Cisco IP Voice Media Streaming Application The Cisco IP Voice Media Streaming Application provides voice media streaming functionality for Cisco CallManager for use with MTP, the annunciator, conferencing, and MoH. The Cisco IP Voice Media Streaming Application relays messages from Cisco CallManager to the IP voice media streaming driver. The driver handles the Real-Time Transport Protocol (RTP) streaming.
• Cisco MoH Audio Translator The Cisco MoH Audio Translator service converts audio source files, which can be in .WAV or .MP3 format, into the appropriate MoH source file for various coder-decoders (codecs) so that the MoH feature can use them.

To activate the required services in Cisco CallManager, access the administration web page and choose Application > Cisco CallManager Serviceability. In the Serviceability window, choose Tools > Service Activation. You can activate the services on any server that you choose.