[SR-Users] RTPEngine call associations

[Alex Balashov]

Hi,

When using a single RTPEngine, or a single RTPEngine per set, it is 
possible to make stateless RTPEngine calls from Kamailio, since 
everything is keyed by Call-ID + tag.

In other words, one can set up a call, answer it, restart Kamailio, and 
still send a 'delete' to RTPEngine successfully because there's no 
runtime state that needs to persist within Kamailio.

How does this work with multiple RTPEngines in a set? There is clearly 
some runtime state being kept to map (Call-ID, tag) => <RTPEngine 
instance within a set>, otherwise successive stream management commands 
would be round-robined within the set just like initial 'offer' commands.

I take it this association is lost across Kamailio restarts, since I see 
no mechanism to persist it. Does that mean that subsequent stream 
management commands (e.g. updated 'offer' / 'answer' on re-INVITE, 
'delete' on BYE) are blasted out to all instances within a set 
prophylactically? Or is the recipient instance chosen at random as it 
would be with an initial 'offer' command?

Thanks,

-- Alex

-- 
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
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