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New Member

Problems with ISDN QSIG on 1751

I'm connecting one 1751 on Siemens PBX through ISDN BRI QSIG port.

The IOS is 12.2(4)YH and the problem is that the router are trying to establish a conversation in channel 0 instead 1 or 2. Then the PBX refuse the incoming call.

Is there any way to configure the router to not use the channel 0 to establish a call?

Here goes the debug q.931

1w0d: ISDN BR1/0 Q931: TX -> SETUP pd = 8 callref = 0x00CB

Bearer Capability i = 0x9090A3

Standard = CCITT

Transer Capability = 3.1kHz Audio

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0xA98380

Exclusive, Channel 0 <-------------- {Here happens the problem}

Calling Party Number i = 0x0183, '0713'

Plan:ISDN, Type:Unknown

Called Party Number i = 0x81, '0717'

Plan:ISDN, Type:Unknown

Sending Complete

1w0d: ISDN BR1/0 Q931: RX <- RELEASE_COMP pd = 8 callref = 0x80CB

Cause i = 0x85E418 - Invalid information element contents

1w0d: ISDN BR1/1 Q931: RX <- DISCONNECT pd = 8 callref = 0x0001

Cause i = 0x8090 - Normal call clearing

1w0d: ISDN BR1/1 Q931: TX -> RELEASE pd = 8 callref = 0x8001

Cause i = 0x8090 - Normal call clearing

Cisco Employee

Re: Problems with ISDN QSIG on 1751

Is there a specific reason that YH code is being used?

Try loading 12.2(11) and see if it works.

a 'debug isdn q931' will show the q931 messages where this is exchanged.

New Member

Re: Problems with ISDN QSIG on 1751

Because is the only version that support a NT/TE ISDN interface with QSIG signaling.

Refer to page:

Is there any new IOS version?

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