AT&T Co has teamed with Digital Communications Associates Inc, Alpharetta, Georgia to develop a range of micro-to-mainframe products that will operate over AT&T’s Definity Communications System using high-speed Integrated Services Digital Network lines. The first offering, E78 Plus-ISDN, enables users at remote locations, or local users not directly channel-attached to the mainframe, to access mainframes over ISDN with IBM 3278-79 terminal emulation and file transfer. It can be used with AT&T’s speech+data Digital Communications Protocol or the new AT&T Basic Rate Interface card. It will be available in December at $400.