[SR-Users] Regarding RTP in IMS Networks.

[Badri Ranganathan]

Hi all,

I'll make this question a little clearer.

User 1 ---------------- SBC ----+ other IMS network components ---------------------- User 2
Same scenario 

User 1 Making the call + plays RTP Traffic

User 2 Answering the call + records the RTP Traffic coming from User 1 and does a PESQ voice quality analysis

If user 2, after answering the call, did not play RTP  as well, the SBC will not forward  the RTP from User 1 to User 2. [The media gateways responsible for the RTP traffic is also a part of the IMS network right?]

So why this sort of bi-directional traffic imposition in an IMS Network ?

Thanks,
Badri.

-----Original Message-----
From: Badri Ranganathan 
Sent: 24 February 2015 15:13
To: sr-users at lists.sip-router.org
Subject: Regarding RTP in IMS Networks.

Hi all,

I have a doubt w.r.t media traffic in IMS Networks.
If I have a setting as follows -

User 1 Making the call + plays RTP Traffic

User 2 Answering the call + records the RTP Traffic coming from User 1 and does a PESQ voice quality analysis

I see that User 2 has to play RTP Traffic before it can start recording the RTP coming from user 1.

i.e., User 2 Answering the call + (Play RTP Traffic ) + records the RTP Traffic coming from User 1 and does a PESQ voice quality analysis.

Why am I seeing this behaviour. Is it just a setting in the IMS network that can be changed or is it a standard behaviour in IMS Networks ? If yes, then could anyone please let me know the logic behind such a decision?

Please do let me know if you have any ideas. Any responses  really appreciated !

Thanks,
Badri.