Mino – The UC Guy

Microsoft Unified Communications Blog

Posts Tagged ‘bandwidth calculation’

Lync Server 2010 Media Traffic Network Usage

Posted by Mino on November 5, 2010

“This is RTM pre-release documentation information and subject to change in General Availability (GA) release by December 2010 , I will update this post if any changes are required ”

When planning for media bandwidth usage per scenario, use the following tables, which describe the average amount of bandwidth used per media type.

Audio/Video Capacity Planning, Peer-to-Peer Sessions

image

Audio/Video Capacity Planning, Conferences

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Audio Capacity Planning, PSTN

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The network bandwidth numbers in these tables represent one-way traffic only and take silence suppression into account.

When you calculate the actual bandwidth usage for a certain scenario, it is important to understand the actual media flows, which are as follows:

In a two-party scenario:

  • Users send audio streams only while they speak.
  • Both participants receive audio streams.
  • If video is used, both users send and receive video streams during the entire call.

In a Conferencing scenario (that is, a call with more than two participants):

  • Users send audio streams only while they speak.
  • All participants receive audio streams.
  • If video is used, only two participants upload a video stream at a time (that is, the active speaker and the previous active speaker
  • If video is used, all participants receive video streams.
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Posted in Lync 2010 Client, Lync Server 2010 | Tagged: , , , , | 6 Comments »

OCS 2007 Audio/Video bandwidth calculation

Posted by Mino on October 13, 2008

Medium Min High Quality
Data 56kbps 56kbps
Voice 50kbps 80kbps
Video 50kbps 350kbps
RoundTable (Conference video phone) 50kbps 350kbps

Note that the requirements are cumulative –

Data + Voice + Video =

56 + 50 + 50 = 156kbps (Minimum Quality)

or

56 + 80 + 250 = 386kbps (High Quality)”

Here are some calculations I have used. however the 300KBps is only video stream single direction.  Bidirectional video consists of two streams..

The following formula can provide rough bandwidth consumption estimates for conferencing with Audio / Video.

Note:  Calculation results will be displayed in Mbps

CC = Concurrent Conferences

PPC = Participants Per Conference

 

Conference Type

Bandwidth Consumption Mbps

Audio with Application Sharing

(((CC * PPC)*14KBps)+((CC *PPC)*90KBps))*10^-3

Audio and Video

(((CC * PPC)*14KBps)+((CC *PPC)*600KBps))*10^-3

Another OCS 2007 Audio Bandwidth Calculation

Audio Codec
Frame Size [ms]
Codec payload bit rate
[bits / sec]
Total payload bit rate
[bits / sec]
Actual bit rate
[bits / sec]
Without
redundancy
With
redundancy
RTAudio@16KHz
20
24000
29000
45000
74000
RTAudio@16KHz
40
24000
26500
34500
61000
RTAudio@16KHz
60
24000
25666
31000
56667
RTAudio@16KHz
20
18000
21000
37000
58000
RTAudio@16KHz
40
18000
19500
27500
47000
RTAudio@16KHz
60
18000
19000
24333
43333
RTAudio@8KHz
20
8800
11800
27800
39600
RTAudio@8KHz
40
8800
10300
18300
28600
RTAudio@8KHz
60
8800
9800
15133
24933

Posted in A/V Edge Server, Consolidated Edge, Edge Server, Miscellaneous | Tagged: , , , , , , | 7 Comments »