Multipoint Control Units

Multipoint Control Units, or MCUs as they are more commonly called, allow for multiple participants to interact in a conference. The MCU is in control of the conference and determines what codecs are used, who is a presenter, and which video to show, and it mixes the audio. It is a complicated and critical component in conferences.

The Lync A/V MCU service is a software-based MCU that provides this functionality for Lync endpoints, but traditional video conferencing has used a hardware-based MCU. Polycom has a product called the RMX, and Cisco has their own MCU, previously called the Codian devices while under the Tandberg name. The shortcoming of a hardware-based MCU is that it has a fixed hardware specification and can handle a limited number of total participants.