DS1 protection switching option. Valid values are inhibit, notInhibited and notApplicable. Note that SAPI 0 and SAPI 1 (EOC-TMC) are not switched together. 6.2.1 Facility Protection Switching - Option 6.2.1.1 General The facility protection switching feature enables traffic on a failed DS1 facility to be moved to one or more alternate DS1 facilities. The procedures for implementing DS1 facility protection switching across the Generic IDLC Interface are described in Section 12.6.2. R6-75 [685] IDLC systems shall perform a facility protection switch if and only if that action will restore service. 12.6.2 DS1 Facility Protection Switch - Option DS1 facility protection is an option for IDLC systems. The procedures to be followed when facility protection switching is implemented for the Generic IDLC Interface are presented in this section (see Section 6.2.1 for general facility protection switching requirements). A facility protection switching feature enables traffic on a failed or degraded DS1 facility to be moved to one or more alternate DS1 facilities. R12-609 [1475] When an IDLC system includes the facility protection switching option, a dedicated protection facility with a 1:n arrangement shall be used for the Generic IDLC Interface. R12-625 [1491] The default for facility protection switching shall be notInhibited.