2800 series CCME - lightning strike ISDN issue

davieshuw · ‎09-02-2009

Hi our building was hit by lightning yesterday. Since then our 2800 series has intermittent ISDN issues - cracking - calls being cut off as soon as they are answered.. but then other calls are OK so I dont think my isdn ports are fried.

Here is an ISDN dq931 debug of a failed call - does it mean anything to anyone?

Sep 2 09:32:45.934: ISDN BR0/1/0 Q931: RX <- SETUP pd = 8 callref = 0x01

Sending Complete

Bearer Capability i = 0x9090A3

Standard = CCITT

Transfer Capability = 3.1kHz Audio

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0x89

Exclusive, B1

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

Calling Party Number i = 0x2183, '7854622440'

Plan:ISDN, Type:National

Called Party Number i = 0x81, '462045'

Plan:ISDN, Type:Unknown

Sep 2 09:32:45.946: ISDN BR0/1/0 Q931: TX -> CALL_PROC pd = 8 callref = 0x81

Channel ID i = 0x89

Exclusive, B1

Sep 2 09:32:45.974: ISDN BR0/1/0 Q931: TX -> ALERTING pd = 8 callref = 0x81

Progress Ind i = 0x8188 - In-band info or appropriate now available

Sep 2 09:32:46.974: ISDN BR0/1/0 Q931: TX -> ALERTING pd = 8 callref = 0x81

Progress Ind i = 0x8188 - In-band info or appropriate now available

Sep 2 09:32:47.974: ISDN BR0/1/0 Q931: TX -> ALERTING pd = 8 callref = 0x81

Progress Ind i = 0x8188 - In-band info or appropriate now available

Sep 2 09:32:48.914: ISDN BR0/1/0 Q931: TX -> CONNECT pd = 8 callref = 0x81

Channel ID i = 0x89

Exclusive, B1

Sep 2 09:32:48.970: ISDN BR0/1/0 Q931: RX <- STATUS pd = 8 callref = 0x01

Cause i = 0x82E2 - Message not compatible with call state or not implem

Call State i = 0x07

Sep 2 09:32:48.970: ISDN BR0/1/0 Q931: TX -> RELEASE pd = 8 callref = 0x81

Cause i = 0x80E5 - Message not compatible with call state

Sep 2 09:32:52.914: ISDN BR0/1/0 **ERROR**: L3_ProcessEvent: UNEXPECTED event 9

Sep 2 09:32:52.914: ISDN **ERROR**: Module-l3_sdl_u Function-U19_BadMsg Err.

Sep 2 09:32:52.970: ISDN BR0/1/0 Q931: TX -> RELEASE pd = 8 callref = 0x81

Cause i = 0x80E5 - Message not compatible with call state

Sep 2 09:32:53.970: ISDN BR0/1/0 Q931: TX -> RELEASE pd = 8 callref = 0x81

Cause i = 0x80E5 - Message not compatible with call state

Sep 2 09:32:54.114: ISDN BR0/1/0 **ERROR**: L3_ProcessEvent: UNEXPECTED event 9

Sep 2 09:32:54.114: ISDN **ERROR**: Module-l3_sdl_u Function-U19_BadMsg Err.

Sep 2 09:32:54.970: ISDN BR0/1/0 Q931: TX -> RELEASE pd = 8 callref = 0x81

Cause i = 0x80E5 - Message not compatible with call state

Sep 2 09:32:55.022: ISDN BR0/1/0 Q931: RX <- RELEASE_COMP pd = 8 callref = 0x

Cause i = 0x82D1 - Invalid call reference value

pcameron · ‎09-06-2009

You can see the router sends 2 alerting messages and the attached ISDN network is not happy with this. Normally I would be thinking this is a software issue, but past experience with BRI cards and lightning strikes suggests that your card may have been fried :-(

You may even find that if you do a reload the card no longer shows up in the config at all.

As a FYI, the existing protection mechanisms on the ISDN line side of the VIC2-2BRI-NT/TE interface meet all recognised standards and have worked very well in locations all over the world.

We have, however, observed some cases where BRI cards have been damaged by line surges or external voltage transients.

The VIC2-2BRI-NT/TE card was designed and tested to meet standards for 'on premises' usage. This means that the external NT1 device is expected to provide an adequate level of isolation to prevent common mode voltage pass-through from the Service Provider network side U interface to the Customer Premises terminal side S/T interface.

In this situation, the best course of action would be for the customer to have the Service Provider incorporate a higher level of protection at the cabling entry point to limit external voltage surges from even reaching the NT1 device itself.

This is often referred to as 'direct strike protection' and a good example is detailed in the following Telstra Australia documentation -

http://www.telstra.com.au/abouttelstra/advice/shrieks_thunderstorms/docs/lightning_brochure.pdf

Unless specifically requested, many Service Providers do not install gas discharge tube (GDT) line protection at the cable entry point to the building.

The Telstra Australia ISDN Facilities Manual has additional information on these surge suppressors -

http://www.telstra.com.au/smartcommunity/assets/facilityalteration_1108.pdf

A picture of the surge (lightning) suppressor can be found on page 59. More details on these surge suppressors are on pages 69 and 70.

As mentioned earlier, the VIC2-2BRI-NT/TE card meets all relevant standards and specifications for interconnecting to public networks. There is still a requirement of adequate external line protection at building point of entry, especially in locations that are susceptible to lightning or external transients.

You may want to consider requesting additional line protection on your ISDN services to prevent these kind of problems in the future.