scope:

In accordance with CCITT Recommendation I.420 [5] and ETS 300 102-1 [2] and ETS 300 102-2 [3], this standard specifies the layer 3 access control protocol to be offered by terminal equipment as defined in subclause 1.1.2 at the T reference point or coincident S and T reference point at an interface to a public telecommunications network presented at an ISDN basic access point.

The static attachment requirements and tests specified in this ETS are for TEs having the capability of both originating a circuit switched call and receiving an incoming circuit switched call. In addition, certain TEs of a specialised nature may employ supplementary services as part of their default operation characteristics. The requirements and tests for these specialised terminals are also not covered in this standard.

NOTE: No requirements or tests are included in this document concerning the procedures for packet communications, user-to-user signalling or supplementary services except for the case of the terminal portability supplementary service which can be considered as an essential feature of many ISDN terminals. However, TEs implementing packet facilities, user-to-user signalling or supplementary services may be subject to additional and/or alternative testing by those Administrations whose ISDNs provide the support of packet calls, user-to-user signalling and/or supplementary services.