SONET Access Loop Termination, or SALT, provides loop protection through the use of a Customer Access Ring (CAR) which is terminated in an add/drop multiplexor on the SALT customer's premise. The SALT customer is thereby assured transport protection on the loop. SALT combines potential economies, the efficiency of a higher level of broadband transport, and the inherent self-healing characteristics of a SONET ring.

Since SALT requires SONET transport protection on the user's local loop only, and places no similar requirement beyond the loop piece, services provided via SALT are associated with BA's basic 4 hour service guarantee. A one-minute guarantee is supported when a combined SALT/IDWC solution is sold.

The IntelliLight® Entrance Facility provides loop protection through the use of CAR, terminated in an add/drop multiplexer at the customer's premise.