Vonage Video API Support for Plan B and Unified Plan Session Discovery Protocol


Does Vonage Support Unified Plan SDP?

Applies To

  • Chrome
  • Firefox
  • Safari
  • Plan B SDP
  • Unified Plan SDP


SDP is the mechanism by which endpoints such as client devices, like a phone or laptop, convey information such as the kinds of media supported (audio or video); the media formatsx§ supported (H264, VP8, etc); and hints on how to establish a connection with it.

When two endpoints want to establish a connection, they share SDPs through a negotiation process. After negotiation completes, the endpoints have enough information to (attempt to) start sharing media.

In WebRTC, the two most often used dialects are Plan B and Unified Plan. Google Chrome, and Chromium-based browsers like recent versions of Microsoft Edge, use Plan B. Firefox and Safari use Unified Plan.

Vonage Video has tested interoperability and compatibility with both Plan B on Chrome and Unified Plan in Firefox and Safari. As of 24 August 2021, Google Chrome browser removed support for the Plan B SDP and supports only Unified Plan SDP.

As of August 2021, our platform transitioned Vonage Video clients in browsers to strictly use Unified Plan. This transition happened with a patch release to versions 2.18, 2.19, and 2.20 of the web SDK.

Vonage will continue to release bug fixes if required to currently supported client SDKs to ensure maximum compatibility across all uses of the Video Platform. Users should upgrade to the latest patch releases of their SDK. Users on specific point releases should change configurations to use the latest point release to ensure maximum compatibility.

Applications using Native clients already are capable of understanding both Plan B and Unified Plan formats, and do so when interacting with Firefox and Safari browsers. Native clients with Chrome and Unified Plan have been tested, and found all currently supported clients (2.17+) to function properly.

Additional Information

Users experiencing issues with the deprecation of Plan B may consider registering for the Chrome Origin Trials, which provides a temporary opt-out of Plan B deprecation. For more information, see Subscriber and Publisher Errors Related to Deprecated Support for Plan B.

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