Technical Helpweb

Troubleshooting Diva ISDN Cards

Note: Use the Diva Checklist procedures below for general card configuration issues where the installation has been successful but the Diva 'Line Check' test fails.  

Checklist

If you have installed a Diva card successfully, but have problems getting it working, follow the suggestions outlined in this checklist.

• Run Line Check
• Check Cables
• Check Country / Switch setting
• Check network settings - click here, or select below to go directly to your network settings:
  • Basic Rate, direct to Telco via NT1, Point to Multi Point
  • Basic Rate, via PABX, Point to Point
  • Basic Rate, via PABX, Point to Multi Point
  • Basic Rate, direct to Telco via NT1, Point to Point
• PABX Issues
• Remove other devices
• Test with another device
• Test with another line

Note: After any corrective action is taken, always run Line Check again to see if the correction worked!

Checklist Procedures:

Run Line Check

• Using Line Check

Check ISDN cable and sockets

Ensure the correct cable is being used, and that the cable is fully home in the socket at either end.

Other potential errors are that the Ethernet and ISDN cables have been swapped in error:

• ISDN cable from the socket on the wall is plugged in to an Ethernet card
• ISDN cable from Diva card goes to Ethernet socket on the wall

Check Country / Switch settings in Diva setup:

In Europe, and many other countries, the ISDN protocol used is ETSI-DSS1, commonly known as Euro-ISDN, which is the default setting chosen by the Diva setup wizard. There are a very few notable exceptions, primarily on some old switches from Deutsche Telekom and old PBX's in Germany which use the previous German National standard - 1TR6. Check the settings and try the alternative and see if it cures the problem. Don't forget to reset the settings if the alternative is not the cure for the problem!

If you experience any difficulties, request your ISDN supplier or your PABX supplier to confirm the protocol being used.

It is always recommended to double-check with the telephone company and the PBX manufacturer in case of any doubt.

Note for Diva Server cards ONLY:

With the latest Diva drivers there is now an option 'PBX, Q-SIG' available when you configure the ISDN protocol. This can be used on PBX's which require support for the Q-SIG standard. If you select this option, please note that this is not a completely new protocol, but a 'superset' based on EURO-ISDN (ETSI-DSS1).

Network Settings:

Basic Rate, direct connection to Telco via NT1 wall-socket, point to multi-point connection

• TEI = Automatic
• Connect mode = No disc
• Direct Dial In (NT2) = OFF

Basic Rate, connected to local PABX, with a point to point connection

Connected via wall socket to private exchange (PABX)

• TEI = 0
• Connect mode = No disc
• Direct Dial In (NT2) = ON

Basic Rate, directly connected to Telco with point to point connection

• TEI = 0
• Connect mode = No disc
• Direct Dial In (NT2) = ON

Basic Rate, connected to local PABX, with a point to multi-point connection

• TEI = Automatic
• Connect mode = No disc
• Direct Dial In (NT2) = OFF

PABX

Various problems can arise when connecting a Diva card via a local PABX - see below. It is highly recommended to confirm the correct operation of the Diva card first by using a direct connection from the Diva card to an ISDN line, if available.

Incoming call problems

General configuration issues:

• Make sure there is an application listening for incoming calls (e.g. RAS or fax software)
• Make sure there is only one application listening for incoming calls on a particular MSN

PABX configuration issues:

• The PABX does not adhere fully to international ISDN standards on its internal lines
• Certain ISDN services are not fully enabled (e.g. enabled only for outgoing and not for incoming calls)
• Problems with the mapping of internal and external MSN's, if used (depends on the PABX)
• Incorrect ISDN protocols configured
• Special protocols are enabled (e.g. QSIG), which require supplementary services
  (which may not be fully supported by the Telco or need to be specifically ordered)

Outgoing call problems

• A necessary dial-prefix is not being used, or is incorrect (e.g.0 or 9 is required before the actual number)
• There could be special features (PABX filters) enabled, which prevent making outgoing calls via all, or specific, MSN's. For example, all international phone numbers, or phone numbers with certain area codes.
• Some older PABX firmware / software versions require an upgrade to function correctly.
  
  If there are problems with incoming and outgoing calls then there is likely to be a mixture of the issues mentioned above.

Remove other ISDN devices, if present

Are there other devices also connected to the ISDN line (fax, etc)? If so, try removing all other devices and run Line Check again. If removing other ISDN devices results in successful operation of the Diva card, then there is likely to be a TEI addressing issue.
For TEI addressing rules refer to the Eicon Networks online ISDN course:

•  ISDN: Theory and Practice  

Test line with another ISDN device which is known to be working, if available

Is there another ISDN device available which is known to be operating successfully? If so, disconnect the Diva device, connect up the other device and see if it works. (If it is another Diva device, then you can use Line Check to test it.) If the device does not work, or Line Check is unsuccessful, then there would appear to be an issue with the line itself, and this needs to be checked by the appropriate technical personnel. If the new device works OK, then the issue is likely to be with the original card and this is the area to concentrate on. 

Test Diva device on other ISDN line, if available

If there is not another device available for testing, is there another ISDN line available? - preferably one with a direct connection to a Telco rather than through a PABX. Run Line Check again. If the result is successful, there may be an issue with the other ISDN line, or the Diva card may have inappropriate settings for that line. Check with the appropriate technical personnel. If Line Check is unsuccessful, then the issue would appear to be with the card rather than the line.