If we desire to connect more than 2 sites in a single video conferencing
session, then we need a device called Multi Conferencing Units
[MCU]. Some manufacturers now provide MCUs in-built in their systems
and can connect upto 6 sites in one session. However, if one desires
for more flexibility and/or more sites to be connected, then an
external MCU is required.
To handle live video and audio links between three or more locations,
the H.323 standard introduces the concept of a Multipoint Control
Unit (MCU). The MCU can be thought of as a “video bridge".
The MCU connects to the Internet and registers with the gatekeeper.
A MCU, depending on its design capacity, can handle a certain
number of simultaneous videoconferences each with each videoconference
being logically separate from the others and with each having
a specified number of users.
When users want to join a particular videoconferencing
session, they dial the service number/password combination. The
gatekeeper checks to see if that service has been registered by
a MCU. The gatekeeper completes the call by connecting the client
to the specified videoconference on the MCU.
The flexibility of these devices is amazing and makes a multi
conference VC session look like child’s play. Not only can
you add and drop participants with a few clicks, you can also
organize a separate and private session for few participants within
a conference. There is theoretically no upper limit to the number
of sites that can be connected simultaneously provided the adequate
bandwidth and the end points are available. The MCUs are capable
of connecting sites across varying networks (ISDN and IP) and
also across varying bandwidths.
- Connect multiple VC locations using
- Any Codec!
- Any Speed!
- Any Layout!
- 3G/GPRS Gateway options - to include cell phones
- Built-in streaming server available
- Firewall solutions available
- CIF/4CIF resolution
- Bandwidth per site - up to 4 Mbits/s
- VC Processing done per port
- Continuous Presence, Transcoding & Rate Matching are
Polycom MGC 25, 50 & 100