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Logic
08-14-2008, 01:33 AM
I have two ITSPs: Pennytel for international & mobile, engin for local. Pennytel only allows one simultaneous outbound call (unless I adopt a more expensive plan), and engin allows multiple calls. So I want Pennytel to fail over to engin when Pennytel is in use...

... but if I call two Pennytels simultaneously where the first routes to mobile and the second to international, or vice versa, the second call fails: "this account is already in use". It's supposed to fail over to engin. Here's what happens instead:

. the Quadro INVITEs the second call, gets the usual 100 Trying and 401 Unauth., then re-INVITEs with authentication
. Pennytel replies 100 Trying Progress, 183 Progress
. I hear audio from Pennytel (I think) saying “this account is already in use”
. then Quadro hangs up, ie CANCELs

14:46:03 TLayer::MsgToTU # Msg type: 183 # TID: 2014 # DID: 2012
14:46:03 SipSessDlg::Inc1xxProc # Got 183 message # OID: 2012 # SID: 460833283...
14:46:03 UA --> CM # Ringing # media exist # SID: 460833283...
14:46:13 CM --> UA # OnCloseCall # OID: 2012 # SID: 460833283...
14:46:13 TLayer::RequestCanceling # Transaction 2014 canceled
14:46:13 Try to send SIP message # (14/08/2008 04:46:13:535 GMT) # UDP # 486 bytes # buff size 0 # from: 192.168.1.30:5060 # to: 203.166.6.160:5060
*****************************
CANCEL sip:04xxx@sip.pennytel.com SIP/2.0

My routing is essentially:

4: 04?* IP-PSTN sip.pennytel.com:5060 Any 10; Mobile
5: 04?* IP-PSTN byo.engin.com.au:5060 System Failure 15; Mobile multi
6: 0011?* IP-PSTN sip.pennytel.com:5060 Any 10; International
7: 0011?* IP-PSTN byo.engin.com.au:5060 System Failure 15; International multi

where 04?* is mobile, 0011?* is the international prefix

Pennytel is configured with Multiple Logins unchecked.

Two observations:

. there are no Statistics of the second unsuccessful call for either of the extensions used to place the calls
. if I call two international OR two mobiles simultaneously, the fail over rules work and the second call goes to engin

What’s wrong please: why can’t I make multiple calls on different routes?

KSComs
08-14-2008, 04:32 AM
You might want to remove the "MULTIPLE LOGONS" tag under the Call Routing menu for the VoIP outbound account.
Unchecking this will automatically fail over any call to the next route for the path.

Regards

Kevin

Logic
08-14-2008, 04:53 AM
You might want to remove the "MULTIPLE LOGONS" tag under the Call Routing menu
Thanks but as mentioned, I have configured Pennytel with Multiple Logons unchecked.

davrays
08-14-2008, 06:44 AM
Well, nothing is wrong: everything works on Quadro as expected... The provider doesn't give any SIP-based indication of the fact that the call cannot be done, so the Quadro cannot know that there is a problem doing the second call. ITSP gives a human-understandable voice message after 183 response, but for Quadro this is just a "Ringing" state, where noone answers. Thus the failover cannot work, as the call is not considered as failed...
Because of the same reason the call is not shown in the Unsuccessful Call Statistics: for the Quadro it was successful attempt to call, where just nobody answered.

Unchecking "Multiple Logons" typically should help in such situations, but that box applies only to the same routing rule: when you uncheck that box, the rule becomes unavailable for the second call. But as in your case the second call is done via another rule, the box cannot help..

The best solution is to make provider give a failure indication another way - not by the voice message, but via normal SIP call setup message.
Another solution is to reconfigure the system to make all calls (both mobile and international) via the same rule with "Multiple Logons" unchecked. You can use "0*", which will cover both "04?*" and "0011?*", or you have to use another dedicated prefix.
The third solution is to buy two accounts on Pennytel and use one for the mobile, and the second for the international ("04?*" will use first account, "0011?*" will use second one; of course, "Multiple Logons" should be unchecked on both).

ssteiner
08-14-2008, 07:45 AM
I guess the problem for the IPTSP (I'm in the same boat but as I have one single rule for 99.x % of the outbound calls things work out much better for me) is that phones don't have a TTS mechanism that they could use to turn a string error message from signalling to a voice prompt that human beings understand(even if phones could show a returned error message on screen, you'd still have the issue for phones without a display). Conversely, having the PBX recognize a voiceprompt is even more out of the question.

Iirc, the ability to set a limit of how many concurrent calls can be made over an account is something that has been added to the todo list. This thread just gave me an idea where this should be placed: rather than having it in the call routing rules, it would be better to have it in the sip account setup in the extensions... that way, the scenario mentioned here would also be covered even though there are multiple rules. Having the limit in the rules only would work as long as there's one rule per account, but even if you have a very simple dialplan, there usually are a few different rules for the same account, so having the limit in the account definition would definitely be more useful. And I don't see much use in having the limit rule based... e.g.2 national calls but only one international call doesn't strike me as a very realistic scenario. Providers are very circuit based so the number of concurrent calls is usually the limit (so that might be another option.. to have the limit apply to only outgoing calls or to all calls over the same account.. this might be the case for business minded IPTSPs - I've never seen a limit over the combined number of incoming and outgoing calls with a residential IPTSP).

KSComs
08-14-2008, 08:27 AM
Thanks but as mentioned, I have configured Pennytel with Multiple Logons unchecked.


Sorry .. i should have put my glasses on and read you multiple logons unchecked

0/

Logic
08-15-2008, 12:35 AM
the call is not considered as failed

Thanks, now I understand what's happening. In effect I had assumed that "Multiple Logons" applies to the SIP account, not to instances of each rule.

I think that my best solution is to sign up for Pennytel's auto recharge billing, which is a (opportunistic) prerequisite for having multiple calls. I can't combine the 04 and the 0011 dialplans as suggested, because those destinations are parsed differently by Pennytel and engin. Also, a comprehensive rule such as 0* could be a problem for PSTN failovers from other rules for local calls etc.


having the limit in the account definition would definitely be more useful

And I agree with this. Without knowing the technical ins and outs, the generally best solution IMO would be for Quadro to control Multiple Logons by counting account sessions rather than rule instances. Surely otherwise many small to medium size Quadro customers are experiencing my problem, perhaps without realising why.

Anyhow, thanks again for excellent support and a great product.

davrays
08-15-2008, 10:50 AM
Hi guys,
regarding Stephan's suggestion:

rather than having it in the call routing rules, it would be better to have it in the sip account setup in the extensions...

I mostly agree, probably we'll change that somewhen later to have the logon limitation on the account. Though the most flexible way is to have that limitation still on the routing rules, but allow to group routing rules to indicate that only one call (or later, a specified number of calls) can be done throgh that group of rules. But I cannot see yet a user-friendly way of configuring such feature: thats feature is difficult to explain, and is even more difficult to develop a friendly way of configuring that..


Anyhow, thanks again for excellent support and a great product.
You're certainly welcome :)

Best regards,
David

ssteiner
08-15-2008, 11:22 AM
But I cannot see yet a user-friendly way of configuring such feature: thats feature is difficult to explain, and is even more difficult to develop a friendly way of configuring that..hmm.. have a small scrollable box that is activated when the limitation is active and where you can select other rules to be grouped together?
Then again I guess it's a valid question if this scenario is indeed needed. Have you encountered an IPTSP which would impose a limit not in the number of concurrent calls, but # of concurrent calls per destination?
Similarly, can you imagine a scenario where a limit on the number of calls spans rules over different accounts (or trunks)? Hmm... actually that could make sense if we think about round robin scenarios and you wanting to reserve a certain number of channels for inbound or outbound calls. Then again.. if one channel goes down.. the rule would need to know that in order to adapt so I guess at the end of the day you'd still end up with one rule per trunk.

esscom
03-31-2009, 05:00 PM
Hi,

We are also experiencing the same issue with Pennytel. Are there any immediate plans to introduce this feature in the near future?

Regards
Scott

davrays
04-01-2009, 04:34 PM
Nop, no immediate plans for that. This issue is specific for Pennytel, the behaviour of that service is not standard and is not welcome. The most of ITSPs vare behaving more inteligently, giving normal SIP indications. Thus this issue is not considered as urgent by us, especially that there are workarounds mentioned above.
So the impovement with call number limitation is still in our plans, but is not near the top of the list...

Best regards,
David