ISDN disconnect

j.huizinga · ‎04-02-2008

Hi,

I have a callmanager 4.1 and a 1760 with some BRI's under MGCP control. Someone cannot call us. After some debugging I have seen the following:

Good call:

ISDN BR0/0 Q931: RX <- SETUP pd = 8 callref = 0x1F

Sending Complete

Bearer Capability i = 0x9090A3

Standard = CCITT

Transfer Capability = 3.1kHz Audio

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0x8A

Progress Ind i = 0x8483 - Origination address is non-ISDN

Calling Party Number i = 0x0183, '210xxxxxxx'

Plan:ISDN, Type:Unknown

Called Party Number i = 0xC1, '64xxxxx'

Plan:ISDN, Type:Subscriber(local)

ISDN BR0/0 Q931: TX -> CALL_PROC pd = 8 callref = 0x9F

Channel ID i = 0x8A

ISDN BR0/0 Q931: TX -> CALL_PROC pd = 8 callref = 0x9F

Channel ID i = 0x8A

ISDN BR0/0 Q931: TX -> ALERTING pd = 8 callref = 0x9F

Progress Ind i = 0x8088 - In-band info or appropriate now available

ISDN BR0/0 Q931: TX -> CONNECT pd = 8 callref = 0x9F

ISDN BR0/0 Q931: RX <- CONNECT_ACK pd = 8 callref = 0x1F

ISDN BR0/0 Q931: RX <- RELEASE pd = 8 callref = 0x1F

Cause i = 0x829A - Non-selected user clearing

ISDN BR0/0 Q931: RX <- RELEASE pd = 8 callref = 0x1F

Cause i = 0x829A - Non-selected user clearing

ISDN BR0/0 Q931: RX <- DISCONNECT pd = 8 callref = 0x1F

Cause i = 0x8290 - Normal call clearing

Progress Ind i = 0x8288 - In-band info or appropriate now available

ISDN BR0/0 Q931: TX -> RELEASE pd = 8 callref = 0x9F

Wrong call:

ISDN BR1/1 Q931: RX <- SETUP pd = 8 callref = 0x27

Sending Complete

Bearer Capability i = 0x9090A3

Standard = CCITT

Transfer Capability = 3.1kHz Audio

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0x8A

Progress Ind i = 0x8183 - Origination address is non-ISDN

Calling Party Number i = 0x0181, '210xxxxxxx'

Plan:ISDN, Type:Unknown

Called Party Number i = 0xC1, '64xxxxx'

Plan:ISDN, Type:Subscriber(local)

Low Layer Compat i = 0x8090A3

ISDN BR1/1 Q931: TX -> RELEASE_COMP pd = 8 callref = 0xA7

Cause i = 0x80E4 - Invalid information element contents

ISDN BR1/1 Q931: TX -> RELEASE_COMP pd = 8 callref = 0xA7

Cause i = 0x80E4 - Invalid information element contents

The difference between these calls is the message: Low Layer Compat i = 0x8090A3

Any idea why I receive this and is there a way to ignore this?

Thanks,

JH

vmoopeung · ‎04-08-2008

Some of the document that can help you are listed below.

http://www.cisco.com/en/US/tech/tk801/tk379/technologies_tech_note09186a008012e95f.shtml

http://www.cisco.com/en/US/tech/tk801/tk379/technologies_tech_note09186a0080093c1a.shtml

jbarcena · ‎04-08-2008

Could you please include more information about the problem?

Is this happening only for incoming calls from the PSTN? What do you hear when you make the call that is not completed?

Are you able to replicate the problem at will?

Is the problem random or does it happen always for the same calling party?

j.huizinga · ‎04-09-2008

Hello Jorge,

It is simple:

It only happens on inbound calls and only from this customer and always.

The customer that calls us hears a busy tone.

Looks to me that they are sending something wrong to me, but they claim they have no problems calling anyone else, except us.

Thanks,

Jan

paolo bevilacqua · ‎04-09-2008

Is not that they are sending anything worng, it that the CM doesn't like the LLC IE as you noted. It is a perfectly legal IE by the way, sometime present when the call comes from a cellphone or via a transit network.

The IE cannot be filtered. Either upgrade or fix the CM to accept it (I sorry, I don't really know how), or configure the GW for H.323 and it would have no problem in receiving the LLC IE.

Hope this helps, please rate post if it does!