31 Dec
2004
31 Dec
'04
12:25 a.m.
At 04:14 PM 12/30/2004, Matt Schulte wrote:
Which was right.
A technique I favor is relying on trustable media gateway. Trustable means
it is in your hands and you can rely on it to detect dead calls (either
by lack of RTCP or using session-timer) and hang up properly.
However, in production environments a CDR mediation devices ideally collects
CDRs from the gateway -- the reasons is that the gateway knows all information
best. All in all, it is the place which provides the service in question.
It knows even media status and PSTN signaling status.
Well -- people may wonder why I am mentioning just the case with PSTN gateway.
What happens if there is no such and it is an IP-to-IP call? My suggestion
is to forget charging and producing CDRs.
-jiri
I don't
like the idea of having 2 or 3 programs in my path.
Neither do I :-) Asterisk is a stateful *ahem* softswitch/proxy, that
always generates a BYE. It communicates directly with whatever it
connects to, unless you redirect of course. I wouldn't use Asterisk for
this purpose of course for many reasons either, I was just making a
point :-) 
31 Dec
31 Dec
8:28 a.m.
New subject: [Serusers] CDR Issues
Jiri Kuthan writes:
Well -- people may wonder why I am mentioning just the
case with PSTN
gateway. What happens if there is no such and it is an IP-to-IP call?
My suggestion is to forget charging and producing CDRs.
i fully agree. this topic has been discussed on the list a few times
already and newcomers can check the archives for details.
-- juha
10:03 a.m.
New subject: [Serusers] CDR Issues
Jiri Kuthan wrote:
At 04:14 PM 12/30/2004, Matt Schulte wrote:
Which was right.
A technique I favor is relying on trustable media gateway. Trustable means
it is in your hands and you can rely on it to detect dead calls (either
by lack of RTCP or using session-timer) and hang up properly.
However, in production environments a CDR mediation devices ideally collects
CDRs from the gateway -- the reasons is that the gateway knows all information
best. All in all, it is the place which provides the service in question.
It knows even media status and PSTN signaling status.
Well -- people may wonder why I am mentioning just the case with PSTN gateway.
What happens if there is no such and it is an IP-to-IP call? My suggestion
is to forget charging and producing CDRs.
-jiri
My problem is that we don't control the SIP to PSTN gateway, so all our
calls are SIP:SIP without the possibility to check the gateway, if one
side hang up it is likely that the other side will create a BYE, however
if both sides are disconnected, we have a problem.
I
don't like the idea of having 2 or 3 programs in my path.
Neither do I :-) Asterisk is a stateful *ahem* softswitch/proxy, that
always generates a BYE. It communicates directly with whatever it
connects to, unless you redirect of course. I wouldn't use Asterisk for
this purpose of course for many reasons either, I was just making a
point :-)
12:01 p.m.
New subject: [Serusers] CDR Issues
At 09:03 AM 12/31/2004, Erik Versaevel wrote:
My problem is that we don't control the SIP to PSTN
gateway,
That appears to me to be a problem of trading costs of different solutions.
What we have been deploying is a system in which you trust a third-party
gateway to generate BYEs and send CDRs to you. The risk of having inaccurate
CDRs depends on reliability and trustworthness of the third party. It seems
to be an acceptable risk -- all in all it is CDRs what they get their money for.
You may wish to introduce an additional source of CDR in your system for sake
of verification -- some kind of call stateful element which observes call status.
However, the costs of such a solution do not appear to me to justify the
benefits -- proxying media, keeping call state, interop issues with calls
on hold or silence detection,and possibly more.
so all our calls are SIP:SIP without the possibility to
check the gateway, if one side hang up it is likely that the other side will create a BYE,
however if both sides are disconnected, we have a problem.
I am not sure if there is a value in a CDR for a call to a gatrway which
exited abruptly.
-jiri
7272
days inactive
7273
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3 comments
3 participants
participants (3)
-
Erik Versaevel -
Jiri Kuthan -
Juha Heinanen