Scope 1.1
General
This standard establishes performance and tech¬nical criteria for interfacing and interconnecting the various functional groups shown in figure 1. Compliance with this standard is intended to ensure compatibiiity at the interface points la and 'b (figure 1) and should not be construed as a constraint on the internal operation of the network, NTs or TEs. For an interim period1), as noted In 5.4.3, equip¬ment that provides a DSX-1 interface arrangement at reference points S and T, shall be considered as conforming to this standard. See annex B for characteristics of a DSX-1 interface.
NOTE - The user's attention is 'called to the possibility that compliance with this standard may require use of an invention covered by patent rights.
By publication of this standard, no position is taken with respect to the validity of this claim or of any patent rights in connection therewith. The patent holder has, however, filed a statement of willingness to grant a license under these rights on reasonable and nondiscriminatory terms and conditions to applicants desiring to obtain such a license. Details may be obtained from the secre¬tariat. The provisions of this standard are Intended to be consistent with applicable requirements concerning safety and environmental condi¬tions. Customer premises equipment (CPE) shall be subject to the applicable requirements of UL 1459, Telephone appliances and equip¬ment 2), and of the rules of the Federal Com¬munications Commission (FCC).
NOTE - Users are advised that CPE for primary rate ISDN may be subject to the FCC's Part 68 Rules, including the provision of output pulse generation capability beyond that required by this standard. Equipment manufacturers should ascertain the applicability of these requirements to their products.
This standard is intended to remain consistent with the American National Standard for Tele¬communications, Carrier to customer installa¬tion - DS1 metallic interface specification (DS 1 standard),
ANSI T1.403-1989. The DS1 stan¬dard contains specifications at the network in¬terface (NI) for services at the DS1 rate. This primary rate (PR) standard defines speci¬fications at physical interface points la and Ib (as shown in figure 1). Criteria covered herein include ISDN channel allocations, framing for¬mat, line code requirements, electrical charac¬teristics, physical requirements, maintenance provisions, and other necessary criteria for:
- compliance with the electrical specifica¬tions at the NI as covered in clause 5 of the DS1 standard, ANSI T1.403. It is important that the electrical specifications applicable to la allow for a cable loss of up to 1.5 dB at 772 kHz between la and the NI as defined in ANSI T1.403, where the associated equ ip¬ment is connected to a public network;
- the proper interfacing of interconnected CPE.
1.2
Structure
Most requirements in this standard apply equally to la and lb. For these requirements, 11 It is expected that this interim provision will be deleted from the next issue of the standard. 2) This standard is currently under development. Contact the secretariat for more recent information.,
ANSI T1.408-1990 there is no reference to an interface point and it is to be understood that the requirements apply at both points. For other requirementsl provisions, the application Is explicitly stated. Requirements applicable at la and Ib imply re¬quirements on the interface cable as stated in clause 10.
