Cisco 7940 Consultative Transfer

[Noah Mehl]

I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is working, but Consultative Transfer is not. Attached is a zip of a pcap of the exchange. One thing to note, I have added "192.168.2.25" as an alias for the domain, as this was required to get the 7940's working in the first place. Any help would be appreciated. Thanks.

~Noah


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[Tony Graziano]

I don't think cisco has ever been workable in a consultative transfer on
Cisco SIP phones. Cisco calls this Semi Attended Transfer. If it were me I
would disable this feature. Its on by default in sipx, but am not sure
anyone is actually maintaining the plugin.

Post by Noah Mehl
I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is
working, but Consultative Transfer is not. Attached is a zip of a pcap of
the exchange. One thing to note, I have added "192.168.2.25" as an alias
for the domain, as this was required to get the 7940's working in the first
place. Any help would be appreciated. Thanks.
~Noah
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[Tony Graziano]

explain the call flow.

the call comes in, is answered and then you try a semi attended transfer to
destination 84001 (assume 8=voicemail for user 4001?). Is your 4.4 install
up to date?

is your description of the call:

attended transfers to voicemail fail using cisco phone? or something else?

Post by Noah Mehl
I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is
working, but Consultative Transfer is not. Attached is a zip of a pcap of
the exchange. One thing to note, I have added "192.168.2.25" as an alias
for the domain, as this was required to get the 7940's working in the first
place. Any help would be appreciated. Thanks.
~Noah
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[Noah Mehl]

Sorry,

Let me expand.

Call flow:

1. Call comes in from external number (quintum connected to PRI) to extension 1717 (Cisco 7940)
2. I answer the call on 1717 (This works great)
3. I press transfer soft key on 1717, then dial 84001, then I hear the voicemail recording of 84001 (At this point there are two lines going on the phone), then I press the transfer soft key again (Phone displays "transfer failed") - I think that's when I get the 400 - Bad Record-Route

Description:

All attended transfers from Cisco 7940 fails. The attached pcap is a transfer to voicemail, but it fails to other extensions, and to external numbers.

I thought that "Semi Attended Transfer" has to do with being able to transfer while the call is ringing? I disabled that feature on the phone, and the "transfr" soft key is still there.

I believe that I'm up to date: 4.4.0-418.gaac6d8

~Noah

On Aug 1, 2012, at 12:24 PM, Tony Graziano wrote:

explain the call flow.

the call comes in, is answered and then you try a semi attended transfer to destination 84001 (assume 8=voicemail for user 4001?). Is your 4.4 install up to date?

is your description of the call:

attended transfers to voicemail fail using cisco phone? or something else?

On Wed, Aug 1, 2012 at 12:11 PM, Noah Mehl <***@tritonlimited.com<mailto:***@tritonlimited.com>> wrote:
I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is working, but Consultative Transfer is not. Attached is a zip of a pcap of the exchange. One thing to note, I have added "192.168.2.25" as an alias for the domain, as this was required to get the 7940's working in the first place. Any help would be appreciated. Thanks.

~Noah


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[Noah Mehl]

Any ideas? Or should I assume attended transfer on Cisco Phones is not going to work? Thanks.

~Noah

On Aug 1, 2012, at 1:19 PM, Noah Mehl wrote:

Sorry,

Let me expand.

Call flow:

1. Call comes in from external number (quintum connected to PRI) to extension 1717 (Cisco 7940)
2. I answer the call on 1717 (This works great)
3. I press transfer soft key on 1717, then dial 84001, then I hear the voicemail recording of 84001 (At this point there are two lines going on the phone), then I press the transfer soft key again (Phone displays "transfer failed") - I think that's when I get the 400 - Bad Record-Route

Description:

All attended transfers from Cisco 7940 fails. The attached pcap is a transfer to voicemail, but it fails to other extensions, and to external numbers.

I thought that "Semi Attended Transfer" has to do with being able to transfer while the call is ringing? I disabled that feature on the phone, and the "transfr" soft key is still there.

I believe that I'm up to date: 4.4.0-418.gaac6d8

~Noah

On Aug 1, 2012, at 12:24 PM, Tony Graziano wrote:

explain the call flow.

the call comes in, is answered and then you try a semi attended transfer to destination 84001 (assume 8=voicemail for user 4001?). Is your 4.4 install up to date?

is your description of the call:

attended transfers to voicemail fail using cisco phone? or something else?

On Wed, Aug 1, 2012 at 12:11 PM, Noah Mehl <***@tritonlimited.com<mailto:***@tritonlimited.com>> wrote:
I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is working, but Consultative Transfer is not. Attached is a zip of a pcap of the exchange. One thing to note, I have added "192.168.2.25" as an alias for the domain, as this was required to get the 7940's working in the first place. Any help would be appreciated. Thanks.

~Noah


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[Tony Graziano]

Is this a fully updated/patched 4.4 system?

Post by Noah Mehl
Sorry,
Let me expand.
1. Call comes in from external number (quintum connected to PRI) to
extension 1717 (Cisco 7940)
2. I answer the call on 1717 (This works great)
3. I press transfer soft key on 1717, then dial 84001, then I hear the
voicemail recording of 84001 (At this point there are two lines going on
the phone), then I press the transfer soft key again (Phone displays
"transfer failed") - I think that's when I get the 400 - Bad Record-Route
All attended transfers from Cisco 7940 fails. The attached pcap is a
transfer to voicemail, but it fails to other extensions, and to external
numbers.
I thought that "Semi Attended Transfer" has to do with being able to
transfer while the call is ringing? I disabled that feature on the phone,
and the "transfr" soft key is still there.
I believe that I'm up to date: 4.4.0-418.gaac6d8
~Noah
explain the call flow.
the call comes in, is answered and then you try a semi attended transfer
to destination 84001 (assume 8=voicemail for user 4001?). Is your 4.4
install up to date?
attended transfers to voicemail fail using cisco phone? or something else?

Post by Noah Mehl
I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is
working, but Consultative Transfer is not. Attached is a zip of a pcap of
the exchange. One thing to note, I have added "192.168.2.25" as an alias
for the domain, as this was required to get the 7940's working in the first
place. Any help would be appreciated. Thanks.
~Noah
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--
~~~~~~~~~~~~~~~~~~
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Telephone: [phone]
Fax: [phone]
~~~~~~~~~~~~~~~~~~
http://www.linkedin.com/pub/tony-graziano/14/4a6/7a4
Ask about our Internet Fax services!
~~~~~~~~~~~~~~~~~~
Using or developing for sipXecs from SIPFoundry? Ask me about sipX-CoLab 2013!
<http://sipxcolab2013.eventbrite.com/?discount=tony2013>
Telephone: [phone]
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Blog: http://blog.myitdepartment.net
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[Tony Graziano]

I think this has been fully discussed on the FreeSWITCH list.

Its really a mechanism of the phone/UA and how it bypasses media to handle
attended transfers.

In your use case the attended transfer is to a FreeSWITCH media server. I
think this is an issue in the sip stack and is found in Cisco phones as
well as some grandstreams too.

I don't think attended transfer will work on Cisco's (from sip 8.2 to 9.3).
There is noone updating the Cisco plugin or maintaining it, cited due to
too many records route issues with each and every sip release lately. If it
were me, and its not, I'd get Poly com phones.
On Aug 1, 2012 9:09 PM, "Tony Graziano" <***@myitdepartment.net>
wrote:

[Joegen Baclor]

This is the record route issue he is facing and this is a known bug on
cisco phones and will remain broken as long as sipx uses record routes
to preserve states. I suggest you put cisco behind an SBC. See
http://www.ossapp.com for a free one.

Post by Tony Graziano
Is this a fully updated/patched 4.4 system?
Sorry,
Let me expand.
1. Call comes in from external number (quintum connected to PRI)
to extension 1717 (Cisco 7940)
2. I answer the call on 1717 (This works great)
3. I press transfer soft key on 1717, then dial 84001, then I hear
the voicemail recording of 84001 (At this point there are two
lines going on the phone), then I press the transfer soft key
again (Phone displays "transfer failed") - I think that's when I
get the 400 - Bad Record-Route
All attended transfers from Cisco 7940 fails. The attached pcap
is a transfer to voicemail, but it fails to other extensions, and
to external numbers.
I thought that "Semi Attended Transfer" has to do with being able
to transfer while the call is ringing? I disabled that feature on
the phone, and the "transfr" soft key is still there.
I believe that I'm up to date: 4.4.0-418.gaac6d8
~Noah

Post by Tony Graziano
explain the call flow.
the call comes in, is answered and then you try a semi attended
transfer to destination 84001 (assume 8=voicemail for user
4001?). Is your 4.4 install up to date?
attended transfers to voicemail fail using cisco phone? or something else?
On Wed, Aug 1, 2012 at 12:11 PM, Noah Mehl
I have a sipxecs 4.4 install with Cisco 7940's. Blind
Transfer is working, but Consultative Transfer is not.
Attached is a zip of a pcap of the exchange. One thing to
note, I have added "192.168.2.25" as an alias for the domain,
as this was required to get the 7940's working in the first
place. Any help would be appreciated. Thanks.
~Noah
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<http://list.sipfoundry.org/archive/sipx-users/>
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~~~~~~~~~~~~~~~~~~
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[Noah Mehl]

Joegen and Tony,

Thanks for the updates. Yes my system is updated. I guess I will look into switching to Polycom phones ASAP. Thanks.

~Noah

On Aug 1, 2012, at 9:31 PM, Joegen Baclor wrote:

This is the record route issue he is facing and this is a known bug on cisco phones and will remain broken as long as sipx uses record routes to preserve states. I suggest you put cisco behind an SBC. See http://www.ossapp.com<http://www.ossapp.com/> for a free one.

On 08/02/2012 09:09 AM, Tony Graziano wrote:

Is this a fully updated/patched 4.4 system?

On Aug 1, 2012 1:19 PM, "Noah Mehl" <***@tritonlimited.com<mailto:***@tritonlimited.com>> wrote:
Sorry,

Let me expand.

Call flow:

1. Call comes in from external number (quintum connected to PRI) to extension 1717 (Cisco 7940)
2. I answer the call on 1717 (This works great)
3. I press transfer soft key on 1717, then dial 84001, then I hear the voicemail recording of 84001 (At this point there are two lines going on the phone), then I press the transfer soft key again (Phone displays "transfer failed") - I think that's when I get the 400 - Bad Record-Route

Description:

All attended transfers from Cisco 7940 fails. The attached pcap is a transfer to voicemail, but it fails to other extensions, and to external numbers.

I thought that "Semi Attended Transfer" has to do with being able to transfer while the call is ringing? I disabled that feature on the phone, and the "transfr" soft key is still there.

I believe that I'm up to date: 4.4.0-418.gaac6d8

~Noah

On Aug 1, 2012, at 12:24 PM, Tony Graziano wrote:

explain the call flow.

the call comes in, is answered and then you try a semi attended transfer to destination 84001 (assume 8=voicemail for user 4001?). Is your 4.4 install up to date?

is your description of the call:

attended transfers to voicemail fail using cisco phone? or something else?

On Wed, Aug 1, 2012 at 12:11 PM, Noah Mehl <***@tritonlimited.com<mailto:***@tritonlimited.com>> wrote:
I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is working, but Consultative Transfer is not. Attached is a zip of a pcap of the exchange. One thing to note, I have added "192.168.2.25" as an alias for the domain, as this was required to get the 7940's working in the first place. Any help would be appreciated. Thanks.

~Noah


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[Michael Picher]

We'll be working on a 'cisco compatibility service' but this will likely be
a commercial component. The thought is that there will be a SBC component
that will supply signaling to the Cisco phone in a manner that it likes
better.

The Cisco phone's SIP implementation, while it might work ok with a call
manager cluster, it doesn't seem to really like to behave like a proper SIP
UA.

Mike

Post by Noah Mehl
Joegen and Tony,
Thanks for the updates. Yes my system is updated. I guess I will look
into switching to Polycom phones ASAP. Thanks.
~Noah
This is the record route issue he is facing and this is a known bug on
cisco phones and will remain broken as long as sipx uses record routes to
preserve states. I suggest you put cisco behind an SBC. See
http://www.ossapp.com for a free one.
Is this a fully updated/patched 4.4 system?

Post by Noah Mehl
Sorry,
Let me expand.
1. Call comes in from external number (quintum connected to PRI) to
extension 1717 (Cisco 7940)
2. I answer the call on 1717 (This works great)
3. I press transfer soft key on 1717, then dial 84001, then I hear the
voicemail recording of 84001 (At this point there are two lines going on
the phone), then I press the transfer soft key again (Phone displays
"transfer failed") - I think that's when I get the 400 - Bad Record-Route
All attended transfers from Cisco 7940 fails. The attached pcap is a
transfer to voicemail, but it fails to other extensions, and to external
numbers.
I thought that "Semi Attended Transfer" has to do with being able to
transfer while the call is ringing? I disabled that feature on the phone,
and the "transfr" soft key is still there.
I believe that I'm up to date: 4.4.0-418.gaac6d8
~Noah
explain the call flow.
the call comes in, is answered and then you try a semi attended
transfer to destination 84001 (assume 8=voicemail for user 4001?). Is your
4.4 install up to date?
attended transfers to voicemail fail using cisco phone? or something else?

Post by Noah Mehl
I have a sipxecs 4.4 install with Cisco 7940's. Blind Transfer is
working, but Consultative Transfer is not. Attached is a zip of a pcap of
the exchange. One thing to note, I have added "192.168.2.25" as an alias
for the domain, as this was required to get the 7940's working in the first
place. Any help would be appreciated. Thanks.
~Noah
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--
~~~~~~~~~~~~~~~~~~
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Telephone: [phone]
Fax: [phone]
~~~~~~~~~~~~~~~~~~
http://www.linkedin.com/pub/tony-graziano/14/4a6/7a4
Ask about our Internet Fax services!
~~~~~~~~~~~~~~~~~~
Using or developing for sipXecs from SIPFoundry? Ask me about sipX-CoLab 2013!
<http://sipxcolab2013.eventbrite.com/?discount=tony2013>
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