This bitmap describes the use of the facili-
ties data link, and is the sum of the capabili-
ties:
'other' indicates that a protocol other than
one following is used.
'dsx1Ansi-T1-403' refers to the FDL exchange
recommended by ANSI.
'dsx1Att-54016' refers to ESF FDL exchanges.
'dsx1Fdl-none' indicates that the device does
not use the FDL.