ISDN Trouble

Far End Won't Answer

1. Have them check their configuration against the information provided by the local phone company.
   1. Switch Type (National ISDN-1, 5ESS or DMS-1000)
   2. SPIDs
   3. LDNs
   4. Auto Answer enabled
      
2. Have another local ISDN number call them.
   1. If that doesn't work have them report trouble to the local phone company.
   2. If it does work, then you have a problem with the long distance carrier.
      
3. Try another long distance carrier.
   1. Precede the phone number with 10222 (for MCI), 10288 (for AT&T) or 10333 (for US Sprint). 
   2. If either of these calls goes through then the carrier has not included this new exchange in the database of the switch that services your calls. Report trouble to your long distance carrier.

    

Far End Can't Call In

1. Check the configuration against the information provided by the local phone company.
   1. Switch Type (National ISDN-1, 5ESS or DMS-1000)
   2. SPIDs
   3. LDNs
   4. Auto Answer enabled
2. Have another local ISDN number call the number.
   1. If that doesn't work report trouble to the local phone company.
   2. If it does work, then you have a problem with the long distance carrier.
3. Have the far-end try another long distance carrier.
   1. Precede the phone number with 10222 (for MCI), 10288 (for AT&T) or 10333 for US Sprint.
   2. If any of these calls goes through than the long distance carrier is probably at fault. Have the far-end report the problem to their long distance carrier.

    

Call Goes Through but No Audio is Transmitted

Generally Sounds Like Hell

1. If it just sounds muffled, then either
   1. You have called at 56K/G.722. Though this is better than a phoner, we have been conditioned to getting even better performance, tough luck.
   2. The acoustics of the local studio/office have problems. This shows up more often in the locations run by public affairs offices. Try to guide them gently toward better audio for the future.
   3. There are minor incompatibilities in the codecs. If they are capable of multiple coding schemes, you might find that a simpler (less demanding coding scheme like G.722) actually sounds better. This is endemic of a larger problem that can be very hard to fix.
2. If it sounds consistently really bad (high noise level) than chances are that you called a 56K location at 64K. Check your setup and call again.

Intermittent Impairments

This can be either chirps in the audio indicating a momentary loss of framing, or brief holes in the audio indicating more of a problem. Both these examples are symptoms of data slip, the two ends of the call are running slightly out of synch.

The only thing to do is to change the path that the call is routed on by replacing the call. The most reliable way of doing this is to have the opposite end place the call.

Phone Company Trouble Numbers

        Ameritech                      800-982-2310
        AT&T Long Distance             800-367-7956
        Bell Atlantic, Boston          617-555-1611
        Bell Atlantic, New York        800-698-2935
        Bell Atlantic, Washington      800-378-2002
        MCI                            800-333-2007
        Pacific Telephone              800-332-1321
        Southern Bell                  800-247-2020
        Southern New England Telephone 888-332-2832
        Southwestern Bell, OK City     405-291-6211
        US West                        800-214-8043