This blog will discuss some of the conferencing capabilities in Cisco Unified Communications. Cisco Unified Communications Manager (CUCM) supports software and hardware conferencing capabilities, but the capabilities are limited when compared to dedicated conferencing solutions.
CUCM is a server-based platform that supports ad-hoc and “meet me” software conferencing features out of the box. Software conferencing is limited to the G.711 audio codec and 48 conference participants by default. CUCM limits the number of conferencing participants to ensure that the audio conferencing mixing capabilities of the IP Voice Media Streaming Application (IPVMA) service does not affect the call processing capabilities of CUCM.
A stand-alone 7845 server dedicated to conferencing capabilities can be tuned to accommodate up to 256 conference participants. The IPVMA call count service parameter would need to be tuned to increase the number of conference participants supported. It is advisable to set the Run Flag of the other IPVMA media resource to “False” if CUCM will be performing a large number of conference terminations.
Mixed mode conferences between different audio codecs (e.g. G.711 and G.729) are normally a requirement in centralized call processing deployment architectures, where branch locations do not have any local call processing resources. Mixed mode audio conferences are supported in hardware (DSPs registered for conferencing) or in the Meeting Place dedicated conferencing platforms (Meeting Place, Meeting Place Express, Meeting Place Express – Video Telephony). G.729 to G.711 transcoders are not supported in conjunction with the software conferencing in CUCM.
CUCM conferencing does not support queuing, reservations, or security. If these features are a conferencing requirement, then Meeting Place rich media conferencing solutions should be considered. Cisco IP phones have a conference list softkey that will display the participants of the conference call by caller ID. The conference controller can then select a conference participant and remove them from the conference with the remove softkey.
Many other conferencing options are covered in the Implementing Cisco Unified Communications IP Telephony, Part 1 (CIPT1 v6.x/7.x) class.
Author: Dennis Hartmann