scope:

This ETS specifies the attachment requirements for layers 1, 2 and 3, for Terminal Equipment (TE), as defined in subclause 4.1, to connect at the T reference point or coincident S and T reference point to a public Integrated Services Digital Network (ISDN) using primary rate access based on the following:

- layer 1 in accordance with ETS 300 011 [1];

- layer 2 in accordance with ETS 300 125 [11];

- layer 3 in accordance with ETS 300 102-1 [8] and ETS 300 102-2 [10].

In addition this ETS specifies those requirements for Electro Magnetic Compatibility (EMC), safety and protection that arise from connection to the ISDN primary rate access interface and that are not covered by generic standards under the EMC Directive (89/336/EEC) or Low Voltage Directive (73/23/EEC).

The Static Attachment Requirements (SAR) and tests specified in this ETS are for Terminal Equipments (TEs) having the capability of both originating a circuit switched call and receiving an incoming circuit switched call.

No requirements or tests are included in this ETS concerning the procedures for packet communications in the D-channel, user-to-user signalling or supplementary services. 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 ETS.

NOTE 1: This ETS is written as an exceptions document and contains the "delta requirements" between the basic access (described in ETS 300 153 [6] and ETS 300 104 [7], which comprise Candidate NET 3) and the primary rate access.

NOTE 2: A possible 31 x B-channel application, where signalling is sent over the D-channel in a different primary rate access, is outside the scope of this ETS.

NOTE 3: The application of the interface for permanent leased lines (reference point C) as defined in ETS 300 011 [1], Annex C, is outside the scope of this ETS.