Partial rerouting not working

[piesio]

Hello everybody
I'm testing an IP Office 9.0 connected on a PRI to an Ericsson switch. We would like to test partial re-routing and I have activated this flag on the IPO, then configured forwarding unconditional on a user. The partial rerouting is active on Ericsson as well.
But, when IPO gets a call from the PRI towards that user, the IPO sends a new SETUP on the same PRI towards the C party. Instead, we would expect IPO to send a FACILITY message instructing the switch to handle rerouting itself.
Obviously with a new Setup the channel is not freed on IPO, and the B number is sent as CLI to C (not A number), which is not what we want.

Any clue what can be the cause of that? Anything that might be related to the user itself? Just saying.

I attach the log for a call

Thanks in advance for your help!

 

[janni78]

Think a monitor trace would be more informative.

It shouldn't require more than to enable it on the Line, you might need to tick in "Force Number Plan to ISDN".

"Trying is the first step to failure..." - Homer

 

[piesio]

Thanks janni78
I have already tried with both "Force Number Plan to ISDN" activated or not. Nothing changes
I can't find any other useful information on the web, since as you said this feature is supposed to be as simple as putting the flag on the Line.

As for the monitor trace, I'll try to take this trace.

 

[IPGuru]

How is you Pri Configured? CPE CO or Q-sig

I would expect Q-sig for networking 2 systems in which case

Default = Off.
Partial rerouting (PR) is an ISDN feature. It is supported on external (non-network and QSIG) ISDN exchange calls. When an external call is transferred to another external number, the transfer is performed by the ISDN exchange and the channels to the system are freed. Use of this service may need to be requested from the line provider and may incur a charge.


if CPE then you would need to look at an IP Office system monitor trace as previously suggested.



Do things on the cheap & it will cost you dear

 

[piesio]

Hi IPGuru
in fact it is CPE so I would expect to work.

I attach a monitor trace, both first leg and second leg involve the PRI (line id 9).

What do you think about?

EDIT: seems like the IPO is sending facility and receives an error, do I understand correctly?

 

[janni78]

FOUND A SHORT CODE - short_code: N - Tel: Ns27778E - Called_Party: 691013655 - Line Group Id: 2

I don't think you can use that shortcode if you want Partial rerouting to work, it should just be N/Dial/N/2

"Trying is the first step to failure..." - Homer

 

[piesio]

Hi
can you please elaborate why do you think it can be related to the short code?
From the logs it seems it applies the short code correctly, in fact the CLI and dialed number are good, furthermore it seems the IPO has sent a facility message, as expected for partial rerouting. But maybe I'm missing something.

Thanks!

 

[derfloh]

Maybe the feature is not enabled on the provider's side.

 

[janni78]

Might help if you have ISDN L3 Tx/Rx enabled in the trace.

"Trying is the first step to failure..." - Homer

 

[piesio]

Hi, here is the trace with ISDN L3

Thanks for your help

 

[janni78]

Have you tried setting the shortcode so it doesn't alter the CLI on forwarded calls?

It seems like the service provider is rejecting the rerouting, and that might be since you're altering the call information.
If the call gets forwarded you want to keep the CLI (in this case restricted), not change it to 027778E.

"Trying is the first step to failure..." - Homer

 

[piesio]

Trying with no CLI altered, the result is the same, I mean the facility message is rejected and the IPO itself setup the forwarded call, so the PRI channel is not cleared.
I really think it could be due to the switch, not to the Avaya...

 

[janni78]

The switch end should be able to tell you why it rejects it.

"Trying is the first step to failure..." - Homer

 

[intrigrant]

Don't search any further, partial rerouting is only supported on H.323 trunks.

 

[derfloh]

It works with BRI as well. Not sure about PRI.

 

[janni78]

I had a customer who used Partial Rerouting on PRI E1.

It's not even available on H.323, they use H450 to accomplish the same thing.

"Trying is the first step to failure..." - Homer

 

[piesio]

Finally the partial rerouting is working fine now, thanks to some settings at Ericsson side. Nothing changed at IPO side.

Just FYI it is working as expected regardless the short code / ARS that is used to deliver the second leg of the call, so I'm still applying the ARS with
N/Dial/Ns27778E/2

 

[piesio]

By the way, the partial rerouting is not working with call transfer (triggered on the phone: call on hold and then transferred to C party), but I have the impression this might be normal. Do you agree?

 

[IPGuru]

I believe you are corrct that this is normal
partial re-routing is intended to avoid tying up lines when an extn is on divert, it all happens during the call setup phase of the connection.

one the call has been answered it is no-longer possible.

you may find that Qsig may work better for you as it may support anti tromboning* depending on the capabilities f each system.


* I am not sure if this is the case with q-sig on the ipo, but is worth a try is supported by your nortel.


Do things on the cheap & it will cost you dear

 

[piesio]

Well, as far as I've read here and in other forums, QSIG does not support partial rerouting, so it doesn't help in my case.