[Sip] Invite without offer

["Aditya Sehgal" <adi.aquarian at gmail.com>]

Hi all,
Is there any practical situation where in an Invite will contain no SDP. 
Lets say A calls B. 
My understanding (albeit limited) of the RFC makes me believe that 200 OK is sent out when B will pick up the phone. Now assuming, the Initial Invite contained no offer (and 100 rel is not supported),the first offer is then sent out at 200 OK .If the return ACK is either dropped in the IP cloud or is delayed, with no media established, the call is essentially useless.

So, is there any situation where it makes sense for a UE to send an Invite without an Offer.

Please correct me if my assumptions are wrong.

Thanks & Regards,
Aditya Sehgal

-- 

Don't take life too seriously....Nobody comes out alive anyway
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