Asterisk Howto: Configure your DID lines

The telco configures how many digits of the telephone number dialled by the caller is sent down to your PBX. Some connections, PRI or BRI, send all digits and some only the part that distincts the number from others, like the four last digits. (note: this can be set to 0).

You need to have an exten entry in extensions.conf that matches the number of digits the telco is sending. You should be able to see this from the command line interface with a couple of verbose flags.

If you are using zap channels, in zapata.conf make sure that immediate=no and with BRI/PRI zap channels set overlapdial=yes . If it is set to immediate=yes then Asterisk will not wait for the telco to send the digits and will do a match with the 's' extension.

Example

When we had a E&M wink T1, the telco sent 4 digits of the phone number,
This meant our exten line looked like;
  exten => 1212,1,answer

Now we have a PRI with full 10 digits passed and have the following exten entry;

  exten => 6155551212,1,answer

See also

• DID: Direct inward dialing
• Asterisk ISDN4Linux: ISDN for Linux (i4l)
• Asterisk CAPI channels
• Asterisk DID mISDN: Utilizing DID with mISDN
• Asterisk ZAP channels
• Asterisk config extensions.conf
• zaptelBRI (zaphfc)

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