What does 'sdparta' stand for in a Firefox webRTC session description?

Back in 2014 five Mozilla developers (including myself) locked them self in an AirBnB for one week to add multi stream support to Firefox. On Monday evening we concluded that it would be impossible to achieve this with the current code base, which at the time contained a full blown SIP stack from Cisco. On Tuesday morning we started ripping out all the code we never wanted to use again and started to replaced it with code written from scratch, but suitable for the more advanced uses cases of WebRTC.

You can imagine that by the end of the week all of us where pretty fed up with the arcane Session Description Protocol. So when Adam opened the bug Byron started to look into the SDP grammar and where it would allow us to put the Firefox version number. That's when we realized that this would be the ideal place to add some fun.

So TL;DR: just a typical Easter egg, where developers wanted to have some fun. Nothing more.

Interesting investigation. The user agent has been added for debugging purposes as can be inferred from the associated bug:

Adam Roach: It would be helpful for debugging if we reported the current Firefox version in our SDP.

and then Byron Campen added a changeset with the user agent and the mozilla...THIS_IS_SDPARTA-<user-agent> line. So, there's most certainly nothing more to it.

To expand on Nils' answer, I don't recall whose idea it was among the five of us, but I think it might have been Martin. The first place it appeared in the code is here in some ASCII art in the rewritten code.

We knew that this rewrite was extreme and risky, but our patience with the current state of the code had finally run out, and the mood in the room was reminiscent of Leeroy Jenkins. So a little bit of silly humor crept into the code.

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