Tuesday, April 14, 2009

Lotus Sametime Bandwidth Consumption

Audio/Video Bandwidth Consumption by Sametime

Use the information below as a baseline; obviously there are a lot of variables that control the ultimate bandwidth used and we can safely assume every customer is different.

We can discern three different bandwidth consuming activities:

  1. Chat or Instant Messaging
  2. Sending files
  3. Screen, slide and application sharing
  4. Using Sametime for Audio and Video purposes

Sending Files:

The amount of data transmitted is highly dependent on the nature of the data itself. Text slides with a plain white background will consume very little bandwidth, whereas fancy slides with lots of images and gradient backgrounds will take up a lot more bandwidth.

Application sharing:

This is essentially just a high resolution video image, with constant updates. Bandwidth will also vary depending on how often users join and leave the conference, since we have to sync up any late joiners with a burst of data.

Slide sharing

Much more efficient than application sharing. In fact, for conferences of 60 users or less, we do not think it would create substantial network load at all.



  1. iSAC: 10-32 kbps (adaptable, average ~20 kbps)
  2. G.711: 64 kbps



  1. SQCIF: 50-100 kbps
  2. QCIF: 100 - 200 kbps
  3. CIF: 300 - 400 kbps


  1. QCIF: 50 - 128 kbps
  2. CIF: 256 kbps
  3. VGA: 512 kbps - 1 Mbps
  4. HD: 1.5 - 4 Mbps

Video resolutions are as follows:

  1. SQCIF: 128 x 96
  2. QCIF: 176 x 144
  3. CIF: 352 x 288
  4. VGA: 640 x 480
  5. HD: 1280 x 720

Please note that all numbers are approximate, and are based on the information we have right now. It may change over time, but this is representative of what we expect.

No comments: