Support: L1,L2 Default: { } Value: Set of ISDN addresses A full set of E.164 ISDN network addresses that a call may be directed in order to reach a network number that matches the address prefix of the parent reachable address entity. Associated with each ISDN network address, but not visible to Network Management, is a variable last failure of type binary absolute time. This attribute is supported only if access type is ISDN DA.