Presents Bellcore's view of proposed generic requirements for ISDN Basic Access Transport System Requirements. The document was reissued to incorporate changes & additions emanating from standards bodies. Some changes include: maintenance bits (aib, sai, uoa) are included in the requirements on the LT, LULT, NT1, LUNT & LUTI; requirements have been added to implement the NT1 Test States; values have been provided for bit error ratio, jitter & delay for the LT, LULT, & LUNT; treatment of certain maintenance bits by line units has been clarified, requirements for local activation of backloops at the LT, LULT & LUNT have been removed; the requirement for Idle Code has been changed to make it consistent with T1.605-1989.