Specifications

MBG Engineering Guidelines, Release 8.0

For the teleworker example:

20 * 1 Kbps + 9 * 24 Kbps + 20/12 * 20 Kbps

= 270 Kbps

For the call center example:

1000 * 1 Kbps + 583 * 24 Kbps + 1000/12 * 20 Kbps

= 16659 Kbps or 16.27 Mbps

Video Calculation

Some VoIP devices support video as well as voice, and extra bandwidth must be provisioned if video calls will be

made. Although the exact bandwidth required depends on the content of the image, number of frames per

second (fps), the codec and compression selected, and the video resolution, the list below gives approximations

for some typical video streams.

Codec Resolution FPS Bandwidth

H.263 or H.264 QCIF (176x144) 15 ~ 128 kbps

30 ~ 256 kbps

CIF (352x288) or QVGA (320x240) 15 ~ 384 kbps

30 ~ 768 kbps

MPEG-4 CIF (352x288) or 320x240 15 – 30 ~ 128 – 360 kbps

This list shows the bandwidth required for video streams from some Mitel devices contrasted with bandwidth

required for other types of media streams.

Voice If compression (G.729a) enabled: 24 Kbps (bi-directional)

If compression not enabled (G.711): 80 Kbps (bi-directional)

MCA Collaboration 192 Kbps (bi-directional)

UCA Video 256 Kbps – 1600 Kbps (bi-directional)

UC360 Video 512 Kbps – 1500 Kbps (bi-directional)

Note: A video call requires 10 to 20 times more bandwidth than a compressed audio call even when

configured with the lowest bandwidth settings.

The Internet bandwidth provisioned at the MBG server must take into account the maximum number of

simultaneous video calls from the remote devices and applications.

When a UC360 initiates a video conference it will also serve as the video bridge for the conference. For

example, a UC360 that is acting as a video bridge for a 4 party conference will require three times the video

bandwidth and three times the audio bandwidth required by a UC360 that is only a participant in the conference.

Video calls between UCA 6.0 and UC360 2.0 are supported through MBG but they do not negotiate bandwidth at

the time of writing. For example, a UCA client on the Internet will receive video at the rate configured on a

UC360 on the LAN even if the UCA is configured to use low bandwidth. This will be rectified in a future release of

UCA and/or UC 360.