# Does Streaming Engine require the control attribute in SDP to have a certain format?

**URL:** <https://community.wowza.com/t/does-streaming-engine-require-the-control-attribute-in-sdp-to-have-a-certain-format/55176>\
**Category:** Wowza Streaming Engine\
**Created:** [May 14, 2020, 6:11pm UTC](https://community.wowza.com/t/does-streaming-engine-require-the-control-attribute-in-sdp-to-have-a-certain-format/55176 "2020-05-14T18:11:34Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![David\_Messer](https://avatars.discourse-cdn.com/v4/letter/d/5f8ce5/32.png) [@David\_Messer](https://community.wowza.com/u/David_Messer)\
**Post date:** [May 14, 2020, 6:11pm UTC](https://community.wowza.com/t/does-streaming-engine-require-the-control-attribute-in-sdp-to-have-a-certain-format/55176/1 "2020-05-14T18:11:34Z")

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I’m pushing video to a Streaming Engine and passing the SDP to the Streaming Engine via the RTSP ANNOUNCE. The server that is delivering the video provides an SDP with a session level control of

a=control:rtsp://192.168.125.101/livePreviewStream and media the media level control is

a=control:rtsp://192.168.125.101/livePreviewStream/video/480p

Based on my limited understanding of SDP, I think the RFC indicates this is okay. However, the Streaming Engine reports “RTSPCore.setup: track missing: 480p”.

If I replace the control attributes with the following, it works fine:

a=control:\*

a=control:streamid=0

I’ve tried different variations, but the above seems to be the only thing that works. Is this a required format of the SDP for the Streaming Engine?

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**Author:** ![Rose\_Power-Wowza\_Com](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/rose_power-wowza_com/32/431_2.png) [@Rose\_Power-Wowza\_Com](https://community.wowza.com/u/Rose_Power-Wowza_Com)\
**Post date:** [May 18, 2020, 5:40pm UTC](https://community.wowza.com/t/does-streaming-engine-require-the-control-attribute-in-sdp-to-have-a-certain-format/55176/2 "2020-05-18T17:40:00Z")

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Hi @David Messer, it looks more like the transport is not specified, so when using \* Wowza Streaming Engine defaults the format so it works - but when you set the URI we don’t default it - so it doesn’t work - we would need to see the full SDP to be sure. Can you send us a support ticket so we can take a closer look and test this? Thanks.

[https://www.wowza.com/support/open-ticket](https://www.wowza.com/support/open-ticket)