Video Conferencing Bandwidth
Video Conferencing Bandwidth Requirements
Video Conferencing is a bandwidth intensive application. This is especially true for High Definition (HD) video quality. The below table provides information on what quality video can be expected relevant to IP bandwidth on some common systems. This is only applicable if IP will be utilized for video conferencing connectivity.
Data Rate Support Resolution for Video Conferencing Bandwidth
- 128K 432 x 240 (WCIF)
- 384K 912 x 512 (Higher than 480p DVD quality)
- 512K 1088 x 720 – 2 x DVD Quality
- 768K 1280 x 720 (720p30) – HD @ 30 fps
- 1.1Mb 1280 x 720 (720p60) – HD @ 60 fps
- 1.7Mb 1920 x 1080 (1080p30) – Full HD @ 30 fps
It should be noted that when initiating a video call on an IP connection, there is an additional 20% IP overhead required.
For example, when initiating a video call at 384Kbps, the actual bandwidth that will be used and required is ±461Kbps OR when initiating a video call at 1Mbps, the actual bandwidth required is ±1.2Mbps.
The above must be taken into account when establishing IP bandwidth requirements.
It is recommended that at least 1Mb dedicated, synchronous bandwidth be provisioned for each site for an optimized experience, 512Kbps for a pleasant experience, 384Kbps for an experience that is “okay”.
Therefore, for an optimized Video Conferencing Experience:
If an HD Video Conferencing Systems is specified, they are capable of up to HD 720p, 1 Mb is preferred, 768kbps is good if it is quality bandwidth, 512kbps is acceptable and 384Kbps is “okay”..
As an alternative, it may be beneficial to utilize a Cloud-Based Infrastructure Solution; please keep in mind the Cloud-Based Solution has its own bandwidth considerations, including that the bandwidth used is currently international when in a multi-party call (3 or more sites) and in an MPLS or similar setting with a single internet breakout (or limited internet breakout), the internet constraints could be limiting and are a primary factor in making a decision regarding VC systems selection. A thorough examination of current bandwidth, exploring options for reallocating bandwidth, or provisioning additional or alternate bandwidth should all be considered when choosing the appropriate solution for Video Conferencing to multiple sites.
ADSL is never the recommended or preferred method of connectivity for use in Video Conferencing. The primary argument against use of ADSL in Video Conferencing is as follows:
- ADSL is asynchronous, therefore the download speed is usually much higher than the upload speed. Video Conferencing requires a sufficient amount of upload speed and synchronous bandwidth, or near synchronous bandwidth, is preferred/required.
- ADSL has no “QOS” or Quality of Service which means that you cannot properly prioritize traffic with packet labelling and it means that the service quality levels and usability cannot be controlled and guaranteed by the provider.
- ADSL is usually a highly contended service – therefore the rated speed and the actual speed are often quite different. Further, the contention is unpredictable and varies by time of day, day of week and location. This variability makes it very difficult to specify ADSL as a reliable method of making Video Conferencing Calls.
- While we do have clients who utilize 4Mb ADSL connections to accomplish Video Conferencing, the quality varies widely and the experience is unpredictable- some are happy, others are not.
We have seen a variety of alternatives to ADSL that work well with varying degrees of quality and price. Alternatives to ADSL:
- First Prize is a dedicated Diginet Connection. It is pricey, but generally provides the most reliable highest quality of service.
- NeoTel NeoBroadband Fiber has thus far shown to be a good alternative at a reasonable price. This service currently works, we’ll see how well it works as more adopt the service and contention ratios increase.
- NeoTel NeoBroadband WiMax has thus far shown to be a good alternative at a reasonable price. This service currently works, we’ll see how well it works as more adopt the service and contention ratios increase.
- Vodacom WiMax has thus far shown to be a good alternative at a reasonable price. This service currently works, we’ll see how well it works as more adopt the service and contention ratios increase.
- iBurst and its subsidiary have some offerings that might make sense including Metro Fiber and Microwave Links, however, they do come at a price. There Broadband and WiMax offering have not been tested by us, but they may work well as well.
- Other less mainstream solutions could be reasonable including localized Mesh Networks and other offerings.
- ADSL is a last resort.
- 3G is too location dependent and much too costly for reasonable service in a fixed location Video Conferencing installation; we have seen it give a mixed set of results in mobility applications ranging from superior to inferior.
- ADSL is never the recommended solution for connectivity.