11 Jan
2008
11 Jan
'08
10:03 a.m.
Andreas Granig schrieb:
Jerome,
In my opinion it depends on the policy of the VoIP provider rather than
on technical issues.
Proper implementation of RFC 4028 of all involved UACs might render RTP
analysis useless, if it's in line with the policy of the the VoIP
provider to have some minutes of tolerance in their CDRs in case of
missing BYEs (the tolerance can be controlled by the provider via the
defined headers). If that is still unacceptable by a provider, there
maybe should be some SIP/RTP-aware billing engines in place though.
Yes. If you do accounting for billing purpose, you should the accounting
where the costs happen and were you have reliable CDRs.
E.g. if you have you own PSTN gateway I recommend doing accounting on
the gateway. The gateway always knows the SIP state and the RTP state.
Further, the gateway should have RTP timeout and/or Session Timer
support to detect dead sessions.
If do you not have your own PSTN gateway but use some PSTN gateway
provider then you either trust the gateway provider and use the CDRs of
the gateway provider or put a B2BUA between your SIP proxy and your
gateway provider (thus the B2BUA is somehow a gateway to the PSTN
provider) and do accounting on the B2BUA.
Doing accounting on the sIP proxy and RTP proxy works too if the gateway
can detect dead sessions - neverthless the CDRs wont be as accurate as
the CDRs from the gateway.
Regarding accounting of SIP-to-SIP calls - if you do not bill them then
you can use accounting on the SIP proxy for statistical reasons. if you
want to bill them, the same as above applies.
regards
Klaus
Andreas
Jerome Martin wrote:
On Thu, 2008-01-10 at 20:10 +0100, Iñaki Baz
Castillo wrote:
_______________________________________________
Users mailing list
Users(a)lists.openser.org
http://lists.openser.org/cgi-bin/mailman/listinfo/users El Jueves, 10 de Enero de 2008, Jerome Martin
escribió:
What, you're not even arguing ? :-) You're too kind.
But seriously, this is a pretty hot subject, and I've never met anyone
suggesting the same as I did here, most of the time I hear the same
thing about rtpproxy + CDRs reliability.
I'm sure some people are challenging what I wrote right now, in their
mind ! If we are lucky, we'll even get emails !
Disclaimer: the above paragraph was not meant to start a flame war on
the topic between SST/pinging schools and RTP detection ones. At worst,
the two techniques can really complement each other.
Regards, To summarize, I'd say that if you rely on RTP
detection for billing,
then you have the following limitations :
- unreliable problem detection
- stuck with RTP proxying for ALL calls
- problems with VAD
- problems in corner cases with re INVITES changing the RTP stream
extremities
What do you think ?
I think that I should thank to you for a great explanation ;)