This topic describes how local conference bridges can reduce IP WAN bandwidth consumption
A local conference bridge at the remote site keeps RTP streams away from the IP WAN for conferences that host only remotely located participants. Use MRGLs to control which phones use which conference bridge.
You can use the same solution for MTPs.
The figure illustrates how local conference bridges can keep voice and video traffic off the IP WAN.
As shown in the figure, if a local conference bridge is deployed at the remote site, it keeps voice streams off the IP WAN for conferences in which all members are physically located at the remote site. You can implement the same solution for MTPs. MRGLs specify which conference bridge (or MTP) should be used and by which IP phone.
This topic describes how transcoders can reduce IP WAN bandwidth consumption.
If a device supports G.711 only, transcoders enable low-bandwidth codecs to be used over the IP WAN.
The figure illustrates how you can use transcoders to reduce the bandwidth that is required on the IP WAN.
In the example, a third-party voice-mail system that supports only G.711 is deployed at the main site. One Cisco Unified Communications Manager server provides a software conference bridge (which also supports G.711 only). If remote phones are configured to use G.729 over the IP WAN, they cannot join conferences or access the voice-mail system. To allow these IP phones to use G.729 and to access the G.711-only services, you deploy a hardware transcoder at the main site.
Remote IP phones now send G.729 voice streams to the transcoder over the IP WAN. The transcoder changes the stream to G.711 and then passes it on to the conference bridge or voice-mail system.
Mixed Conference Bridges
This topic describes how mixed conference bridges can reduce IP WAN bandwidth consumption
Mixed (hardware) conference bridges enable low-bandwidth codecs to be used by remote conference participants.
The figure shows how a hardware conference bridge in mixed mode can be used to reduce the bandwidth that is required on the IP WAN.
In this example, a hardware conference bridge is deployed at the main site. The hardware conference bridge is configured to support mixed conferences, in which members use various codecs. Headquarters IP phones that join the conference can use G.711, while remote IP phones can join the conference using a low-bandwidth codec.