SDP Changes and Their Impact on WebRTC

 Highlights

 Impact on my application

 Standardization status

 

 Highlights

SDP is being improved. It is a slow process but it is happening.

These changes are not only for WebRTC but they impact it.

The improvements are intended to “fix” some limitations in current SDP RFC.

An example of such a limitation is being able to use real numbers instead of integers. One use for this could be for video frame rates. Today you can specify frame rate in integers only but in some cases it is required to use non integers for this parameter.

Another example of such a change is allowing or disallowing 0 in various places.

If these sound like small details, they are. Having said that, there are applications that do “SDP munging” and change SDP before it is sent over the wire (and once received at the other end) in order to work around such limitations.

 Impact on my application

Impact is twofold:

  • Once changes are finalized and implemented you might not need to implement your workaround in SDP
  • If your system is a GW to existing, older VoIP systems that use SDP you need to make sure you are normalizing SDP between both sides

 Standardization status

These changes will take time. Stay tuned to our updates.