ISDN Switch-type

In order for any ISDN lines to establish Layer-1 connectivity the switch-type has to be defined correctly.

The switch-type is very much country dependant so it’s also important to memorize the switch-type that applies to where you do most of your installations.

If Layer-1 is showing ‘Deactivated’ when using the show isdn status command, only 3 things can be the source of the problem.

  1. isdn switch-type has not been set, or has not been set correctly (The most common problem)
  2. There is a problem with the PSTN (call your telephony service provider)
  3. Cable problems
  4. Physical port failure on the Router.

In order to configure the switch-type you can enter the command

Isdn switch-type {switch-type}

This can be done either in global configuration mode, or on the interface depending on the router and IOS version.

Below are all the switch-type options available 



basic-1tr6German 1TR6 ISDN switches
basic-5essAT&T basic rate switches
basic-dms100NT DMS-100 basic rate switches
basic-net3NET3 ISDN and Euro-ISDN switches (UK and others), also called E-DSS1 or DSS1
basic-niNational ISDN-1 switches
basic-nwnet3Norway Net3 switches
basic-nznet3New Zealand Net3 switches
basic-ts013Australian TS013 switches
noneNo switch defined
nttJapanese NTT ISDN switches (ISDN BRI only)
primary-4essAT&T 4ESS switch type for the U.S. (ISDN PRI only)
primary-5essAT&T 5ESS switch type for the U.S. (ISDN PRI only)
primary-dms100NT DMS-100 switch type for the U.S. (ISDN PRI only)
primary-net5NET5 ISDN PRI switches (Europe)
primary-nttINS-Net 1500 for Japan (ISDN PRI only)
primary-ts014Australian TS014 switches (ISDN PRI only)
vn2French VN2 ISDN switches (ISDN BRI only)
vn3French VN3 ISDN switches (ISDN BRI only)
vn4French VN4 ISDN switches (ISDN BRI only)





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