Re: [MMUSIC] RTSP "alt-ports" are not mentioned in the RFC.

Harald Alvestrand <harald@alvestrand.no> Mon, 17 December 2012 09:22 UTC

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Date: Mon, 17 Dec 2012 10:22:34 +0100
From: Harald Alvestrand <harald@alvestrand.no>
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Subject: Re: [MMUSIC] RTSP "alt-ports" are not mentioned in the RFC.
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On 12/13/2012 11:42 AM, Dushyant Joshi wrote:
> Hello team,
>
> I could see RTSP alt-ports are not defined in either RFC 2326 or RFC 6064
What is the point of defining an RTSP alt-port?

Usually, in port numbers, two is worse than one; one should either have 
a single port or have protocol/uri syntax to describe using any port.

>
> if you see IANA
>
> http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xml
>
> we have defined port 8554 as the alternate RTSP port
>
> rtsp            554/tcp    Real Time Stream Control Protocol
> rtsp            554/udp    Real Time Stream Control Protocol
> rtsp-alt        8554/tcp   RTSP Alternate (see port 554)
> rtsp-alt        8554/udp   RTSP Alternate (see port 554)
>
> The RTSP 2.0 specification is still an Internet Draft and could add text.
>   can we add this as an informative mentioning that there do exist an
> alternative registered port.
>
> Regards,
> Dushyant Joshi
> 91-9886886757
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