RE: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread Chris A. Icide
The issue we have here is not just related to IAX.  If you have Asterisk 
step out of the media stream for any call, you lose the capability to 
determine the status of the call, and therefore lose the ability to track 
the call in your CDR.

Perhaps (at least for the case of IAX transfers or maybe sip registry 
transfers (reinvite from/to a different asterisk server), we need an option 
for centralized CDR record keeping.  At the begining of any transaction, 
create a truly global unique ID for the transaction and log it with the 
central CDR system.  Now pass that Unique ID along to any parties in the 
transaction, and each party updates the central CDR system with any changes 
to the transaction.  In a scenerio like this you would be able to maintain 
accurate CDR records for any calls in which the media stream passes through 
devices supporting the CDR system.  For it to work fully, you'd need to get 
UAs to support it as well (probably would need an RFC and alot of 
prodding), since in some cases calls will be UA to UA after all the initial 
signalling is completed.

-Chris
On 12:32 AM 6/10/2004, Florian Overkamp wrote:
Hi,

 -Original Message-
  Yes. The issue here is that billing information is never correct in
  such a scenario, since the call duration on the registered asterisk
  machine (the one that is kicked from the path) is no longer correct.
  To fix this a notransfer=yes is mandatory, but that defies the
  practicality of having a voip conversation take the shortest path.

 Sure... So, this issue is sort of a bug and it really needs to be
 implemented then!

I'm afraid its not that simple. Unless I'm misunderstanding the concepts of
IAX(2) design, it does not support such behaviour _by design_. Who knows
what would break if someone hacked our desires in there. A solution then
would be: choose another protocol. Technically you could spin off an
IAX2-cdr channel that supports it, but that would require duplicate efforts
to maintain both channels. My current position is 'deal with it' and accept
the extra traffic. If someone with more knowledge about IAX(2) can comment
on the feasability of this behaviour we may proceed in that direction,
otherwise we're just stuck.

Florian

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Re: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread Andrew Kohlsmith
On Tuesday 15 June 2004 13:53, Chris A. Icide wrote:
 The issue we have here is not just related to IAX.  If you have Asterisk
 step out of the media stream for any call, you lose the capability to
 determine the status of the call, and therefore lose the ability to track
 the call in your CDR.

Is it possible to have a callback whereupon the server that stepped out of 
the way gets notified by one/both of the endpoints as to the call completion 
and so on?

 Perhaps (at least for the case of IAX transfers or maybe sip registry
 transfers (reinvite from/to a different asterisk server), we need an option
 for centralized CDR record keeping.  At the begining of any transaction,
 create a truly global unique ID for the transaction and log it with the
 central CDR system.  Now pass that Unique ID along to any parties in the
 transaction, and each party updates the central CDR system with any changes
 to the transaction.  In a scenerio like this you would be able to maintain
 accurate CDR records for any calls in which the media stream passes through
 devices supporting the CDR system.  For it to work fully, you'd need to get
 UAs to support it as well (probably would need an RFC and alot of
 prodding), since in some cases calls will be UA to UA after all the initial
 signalling is completed.

This is a nice idea, I think -- something akin to a syslog server even.

Regards,
Andrew
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Re: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread Kevin P. Fleming
Chris A. Icide wrote:
The issue we have here is not just related to IAX.  If you have Asterisk 
step out of the media stream for any call, you lose the capability to 
determine the status of the call, and therefore lose the ability to 
track the call in your CDR.
That brings up a question that's been running around in my head... 
imagine this scenario:

User has a SIP phone, sitting behind a NAT.
Asterisk A is their PBX, where their SIP registration goes.
Asterisk B is a PRI server, just handles a PRI (or two) of channels.
A call comes in on the PRI, and is routed from Asterisk B to Asterisk A 
using SIP. The call is then routed by Asterisk A to the SIP phone, and 
the user answers. At this point, both Asterisk boxes are still in the 
media stream.

Since the SIP phone is behind a NAT, and thus canreinvite=no, will 
Asterisk A reinvite Asterisk B _only_, so Asterisk A can drop out of the 
media path?
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RE: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread John Todd
[sorry - too lazy to re-arrange this top-posting stuff]
Not all Asterisk channel types lose control when they step out of the 
media stream.  SIP devices will notify the proxy server (Asterisk, in 
our case) that a call has terminated, so even though the media stream 
never went through the proxy (Asterisk).  This is an important 
distinction between IAX2 and SIP - media and control messages are not 
tightly linked with SIP as they are with IAX2.  Until IAX2 has some 
type of backwards path notification, there is no method (to my 
knowledge) that IAX2 can notify the origin servers that the call has 
been terminated.  The only way for any server in the path to know the 
status of the call (with IAX2) is to not transfer the call away from 
itself, thus bearing the full load of the media stream and the 
control channel.

I would be happy to learn of other's experiences in managing this 
issue, as it is quite important (mandatory, really) in any type of 
managed service environment.

JT

At 10:53 AM -0700 on 6/15/04, Chris A. Icide wrote:
The issue we have here is not just related to IAX.  If you have 
Asterisk step out of the media stream for any call, you lose the 
capability to determine the status of the call, and therefore lose 
the ability to track the call in your CDR.

Perhaps (at least for the case of IAX transfers or maybe sip 
registry transfers (reinvite from/to a different asterisk server), 
we need an option for centralized CDR record keeping.  At the 
begining of any transaction, create a truly global unique ID for the 
transaction and log it with the central CDR system.  Now pass that 
Unique ID along to any parties in the transaction, and each party 
updates the central CDR system with any changes to the transaction. 
In a scenerio like this you would be able to maintain accurate CDR 
records for any calls in which the media stream passes through 
devices supporting the CDR system.  For it to work fully, you'd need 
to get UAs to support it as well (probably would need an RFC and 
alot of prodding), since in some cases calls will be UA to UA after 
all the initial signalling is completed.

-Chris
On 12:32 AM 6/10/2004, Florian Overkamp wrote:
Hi,
 -Original Message-
  Yes. The issue here is that billing information is never correct in
  such a scenario, since the call duration on the registered asterisk
  machine (the one that is kicked from the path) is no longer correct.
  To fix this a notransfer=yes is mandatory, but that defies the
  practicality of having a voip conversation take the shortest path.
 Sure... So, this issue is sort of a bug and it really needs to be
 implemented then!
I'm afraid its not that simple. Unless I'm misunderstanding the concepts of
IAX(2) design, it does not support such behaviour _by design_. Who knows
what would break if someone hacked our desires in there. A solution then
would be: choose another protocol. Technically you could spin off an
IAX2-cdr channel that supports it, but that would require duplicate efforts
to maintain both channels. My current position is 'deal with it' and accept
the extra traffic. If someone with more knowledge about IAX(2) can comment
on the feasability of this behaviour we may proceed in that direction,
otherwise we're just stuck.
 Florian
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RE: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread James Golovich

On Tue, 15 Jun 2004, John Todd wrote:

 
 Not all Asterisk channel types lose control when they step out of the 
 media stream.  SIP devices will notify the proxy server (Asterisk, in 
 our case) that a call has terminated, so even though the media stream 
 never went through the proxy (Asterisk).  This is an important 
 distinction between IAX2 and SIP - media and control messages are not 
 tightly linked with SIP as they are with IAX2.  Until IAX2 has some 
 type of backwards path notification, there is no method (to my 
 knowledge) that IAX2 can notify the origin servers that the call has 
 been terminated.  The only way for any server in the path to know the 
 status of the call (with IAX2) is to not transfer the call away from 
 itself, thus bearing the full load of the media stream and the 
 control channel.
 
 I would be happy to learn of other's experiences in managing this 
 issue, as it is quite important (mandatory, really) in any type of 
 managed service environment.
 

If you depend on behavior of an unspecified client your asking for
trouble. It would be pretty trivial to get a client to send back this
'Call Completed' message right after a re-invite/native bridge has
completed.  If you have access to the source you can modify the client to
do it, or if you have access to the network you have something proxy'ng
the packets and at certain times including or excluding certain messages


James

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread Aaron J. Angel
James Golovich [EMAIL PROTECTED] wrote:
 On Tue, 15 Jun 2004, John Todd wrote:
 Not all Asterisk channel types lose control when they step out of the
 media stream.  SIP devices will notify the proxy server (Asterisk, in
 our case) that a call has terminated, so even though the media stream
 never went through the proxy (Asterisk).  This is an important
 distinction between IAX2 and SIP - media and control messages are not
 tightly linked with SIP as they are with IAX2.  Until IAX2 has some
 
 If you depend on behavior of an unspecified client your
 asking for trouble. It would be pretty trivial to get a
 client to send back this 'Call Completed' message right after

Then the PSTN is broken too.  SS7 (the signalling portion) is separate from
voice trunks.  This was done because it was insecure doing exactly the
opposite -- which put the signalling along with the media, which made
phreaking phun and easy.

IMO, signalling and media should be separate.  The proxying system should
know when the call is complete regardless of whether or not it's in the
media, as proper billing depends on it.  In the PSTN world, it's not the end
users that are responsible for signalling the end of the call; the switches
do that when the media path (i.e., voice trunk) is disconnected.

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread John Todd
At 5:13 PM -0400 on 6/15/04, James Golovich wrote:
On Tue, 15 Jun 2004, John Todd wrote:
 Not all Asterisk channel types lose control when they step out of the
 media stream.  SIP devices will notify the proxy server (Asterisk, in
 our case) that a call has terminated, so even though the media stream
 never went through the proxy (Asterisk).  This is an important
 distinction between IAX2 and SIP - media and control messages are not
 tightly linked with SIP as they are with IAX2.  Until IAX2 has some
 type of backwards path notification, there is no method (to my
 knowledge) that IAX2 can notify the origin servers that the call has
 been terminated.  The only way for any server in the path to know the
 status of the call (with IAX2) is to not transfer the call away from
 itself, thus bearing the full load of the media stream and the
 control channel.
 I would be happy to learn of other's experiences in managing this
 issue, as it is quite important (mandatory, really) in any type of
 managed service environment.
If you depend on behavior of an unspecified client your asking for
trouble. It would be pretty trivial to get a client to send back this
'Call Completed' message right after a re-invite/native bridge has
completed.  If you have access to the source you can modify the client to
do it, or if you have access to the network you have something proxy'ng
the packets and at certain times including or excluding certain messages
James
1) That is true with SIP as well, so the threat is already 
understood.  If the Asterisk server in the middle receives a Call 
Completed message from one side, it should send a Call Completed 
message to the other side, which should (and I use the word SHOULD 
in the RFC meaning) cause the other side to hang up the call if it 
has not already done so.

  If there are two users of the same software package, and they 
conspire to generate bogus Call Completed messages and then ignore 
them, it would be possible for those two users to keep their media 
stream flowing and cheat the Asterisk server in the middle into 
thinking that the call had completed.  However, the media stream is 
not flowing through any Asterisk components, so this risk is limited. 
The trick is that if the same provider controls one side of the 
channel then this is not a problem since the endpoint that is owned 
by the provider would honor the Call Completed message.

  I think my point is it's better to have some information than no 
information in a provider setting.  It is ultimately impossible to 
regulate this if you're billing for it at the call level, but from a 
logging and troubleshooting perspective this is really a good thing 
to have.  The ability (default setting) for IAX2-to-IAX2 calls to 
vanish from the server's perspective after a call is set up will 
cause future heartache from customer service, metrics-gathering, and 
legal perspectives.

2) Any method needs to understand and consider the possibility of 
multiple levels of transferring.  This is the same headache with 
encryption.  If I have an architecture of three or four levels deep 
of IAX2 connections that pass a call between each other, the 
original server probably should somehow have the _option_ of 
keeping track of that call's length and status, and optionally 
closing the call down.  This is not just from a traditional telco 
point of view (billing, fraud, etc) but there are other reasons one 
might want to do this that are non-obvious.  The originating server 
needs to be able to control the status of a call that was passed to 
it without nailing up the media stream.

  I might be wrong here, on two counts: first, that any server in the 
path of reference needs to know the state of a call.  SIP is built on 
a stateless model, but Asterisk is half-stateless - it always keeps 
state for calls that are passing through it, but it tries to get rid 
of those calls as quickly as possible by relinquishing control to the 
clients.  Maybe this is good, maybe it's ultimately flawed.   The 
second place I might be flawed is that maybe we can keep the media 
stream; maybe it's not such a huge burden for what Asterisk is trying 
to do.  G.729 or ilbc are down in the 20 kbps range, so for a system 
that claims to be a PBX, perhaps that's not a big deal.  If this 
claimed to be a softswitch then that would be a problem.  Many 
people are using it as a softswitch, which could cause the 
half-stateless and media relay problems to collide in a very ugly 
explosion of bad CDR's or Gig-E transit connections...

JT
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RE: [Asterisk-Users] CDR for transfered calls

2004-06-15 Thread Senad Jordanovic

I might be wrong here, on two counts: first, that any server in the
 path of reference needs to know the state of a call.  SIP is built on
 a stateless model, but Asterisk is half-stateless - it always keeps
 state for calls that are passing through it, but it tries to get rid
 of those calls as quickly as possible by relinquishing control to the
 clients.  Maybe this is good, maybe it's ultimately flawed.   The
 second place I might be flawed is that maybe we can keep the media
 stream; maybe it's not such a huge burden for what Asterisk is trying
 to do.  G.729 or ilbc are down in the 20 kbps range, so for a system
 that claims to be a PBX, perhaps that's not a big deal.  If this
 claimed to be a softswitch then that would be a problem.  Many
 people are using it as a softswitch, which could cause the
 half-stateless and media relay problems to collide in a very ugly
 explosion of bad CDR's or Gig-E transit connections...
 
 JT

How about producing UA box with * on it and 1-2 fxs/fxo ports. It should
be a complete * system capable of dealing with 2-3 SIP/H323/IAX
channels. Something like Soekris 4801 board stripped down or even some
other CPU to keep the cost down. If box like this can be put together
cost effectively, then this device could be used to be part of complete
global system of * ONLY solution offering complete encryption and
authentication.

Encryption, because one can get each UA to establish required IPSEC
tunnels dynamically where IP SEC tunnels could follow (or rather lead)
media path.

Authentication for purpose of CDR stored locally on UA and centrally.
SSL certificates could be used on each UA to minimise fraud. In another
words, if the media path is set to by pass one or more * servers, then
each UA (originator and terminator) will have a job of dumping CDR
details into their trusted * server after a call is completed.

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-10 Thread Florian Overkamp
Hi, 

 -Original Message-
  Yes. The issue here is that billing information is never correct in
  such a scenario, since the call duration on the registered asterisk
  machine (the one that is kicked from the path) is no longer correct.
  To fix this a notransfer=yes is mandatory, but that defies the
  practicality of having a voip conversation take the shortest path. 
 
 Sure... So, this issue is sort of a bug and it really needs to be
 implemented then!

I'm afraid its not that simple. Unless I'm misunderstanding the concepts of
IAX(2) design, it does not support such behaviour _by design_. Who knows
what would break if someone hacked our desires in there. A solution then
would be: choose another protocol. Technically you could spin off an
IAX2-cdr channel that supports it, but that would require duplicate efforts
to maintain both channels. My current position is 'deal with it' and accept
the extra traffic. If someone with more knowledge about IAX(2) can comment
on the feasability of this behaviour we may proceed in that direction,
otherwise we're just stuck.

Florian

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-10 Thread Senad Jordanovic

 Sure... So, this issue is sort of a bug and it really needs to be
 implemented then!
 
 I'm afraid its not that simple. Unless I'm misunderstanding the
 concepts of 
 IAX(2) design, it does not support such behaviour _by design_. Who
 knows what would break if someone hacked our desires in there. A
 solution then would be: choose another protocol. Technically you
 could spin off an IAX2-cdr channel that supports it, but that would
 require duplicate efforts to maintain both channels. My current
 position is 'deal with it' and accept the extra traffic. If someone
 with more knowledge about IAX(2) can comment on the feasability of
 this behaviour we may proceed in that direction, otherwise we're just
 stuck.

In that case, I suppose we have to put up with it untill it gets to be a
real pain in the neck :)


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RE: [Asterisk-Users] CDR for transfered calls

2004-06-09 Thread Florian Overkamp
Hi, 

 -Original Message-
 Try 
 notransfer=no in iax.conf

Hmm, I assume you mean transfer=no, but that also keeps the voice flow
through the machine. Would IAX2 support having signalling going through all
machines and voice data through the shortest path, more or less like how SIP
works, while keeping the nice NAT/firewall functionality :-)

I would not be surprised if this is impossible by design, but who knows...

Florian

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Re: [Asterisk-Users] CDR for transfered calls

2004-06-09 Thread Holger Schurig
 Would IAX2 support having signalling going through
 all machines and voice data through the shortest path

No, Signalling+Voice is tightly coupled.

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-09 Thread Senad Jordanovic
Holger Schurig wrote:
 Would IAX2 support having signalling going through
 all machines and voice data through the shortest path
 
 No, Signalling+Voice is tightly coupled.

To my knowledge, IAX2 will take shortest route possible. I.e.

A call from UA A to UA C through server B will switch from original path
(ABC) to (AC) and this is default behaviour unless notransfer=yes
exist in iax.conf.

Anyone know for sure?

Ta
Senad

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-09 Thread Florian Overkamp
Hi, 

 -Original Message-
  No, Signalling+Voice is tightly coupled.
 
 To my knowledge, IAX2 will take shortest route possible. I.e.
 
 A call from UA A to UA C through server B will switch from 
 original path
 (ABC) to (AC) and this is default behaviour unless notransfer=yes
 exist in iax.conf.

Yes. The issue here is that billing information is never correct in such a
scenario, since the call duration on the registered asterisk machine (the
one that is kicked from the path) is no longer correct. To fix this a
notransfer=yes is mandatory, but that defies the practicality of having a
voip conversation take the shortest path.

Florian

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-09 Thread Senad Jordanovic
Florian Overkamp wrote:
 Hi,
 
 -Original Message-
 No, Signalling+Voice is tightly coupled.
 
 To my knowledge, IAX2 will take shortest route possible. I.e.
 
 A call from UA A to UA C through server B will switch from
 original path
 (ABC) to (AC) and this is default behaviour unless
 notransfer=yes exist in iax.conf.
 
 Yes. The issue here is that billing information is never correct in
 such a scenario, since the call duration on the registered asterisk
 machine (the one that is kicked from the path) is no longer correct.
 To fix this a notransfer=yes is mandatory, but that defies the
 practicality of having a voip conversation take the shortest path. 

Sure... So, this issue is sort of a bug and it really needs to be
implemented then!

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[Asterisk-Users] CDR for transfered calls

2004-06-08 Thread pesb
Hi there,
I have the following scenario:
I want user A to make a call to user B. If, any of these users transfer the 
call to user C, then asterisk should generate a CDR for the first leg of the 
call. And after the transfered call is finished, asterisk should generate a 
second CDR.
I believe I was able to do it once, a long time ago...
But, I tried this feature again today, and asterisk was generating only one 
CDR (for the transfered call).
Is this possible?
I use aterisk 0.7.2 with Grandstream phones.

thanks in advance,
   Pablo Salinas

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RE: [Asterisk-Users] CDR for transfered calls

2004-06-08 Thread Senad Jordanovic
pesb wrote:
 Hi there,
 I have the following scenario:
 I want user A to make a call to user B. If, any of these users
 transfer the 
 call to user C, then asterisk should generate a CDR for the first leg
 of the 
 call. And after the transfered call is finished, asterisk should
 generate a 
 second CDR.
 I believe I was able to do it once, a long time ago...
 But, I tried this feature again today, and asterisk was generating
 only one 
 CDR (for the transfered call).
 Is this possible?
 I use aterisk 0.7.2 with Grandstream phones.
 
 thanks in advance,
Pablo Salinas
 
Try 
notransfer=no in iax.conf

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