SSH EN 300 403-2 V1.3.1:2000

Rrjeti Dixhital i Shërbimeve të Integruara (ISDN); Sistemi i Sinjalit të Abonentit Dixhital Nr. një protokolli (DSS1); Shtresat e rrjetit sinjalizuese për kontrollin e thirrjes bazë me mënyrën e qarkut; Pjesa 2: Diagramat e Specifikimeve dhe Gjuhës Përshkruese (SDL)

Integrated Services Digital Network (ISDN); Digital Subscriber Signalling System No. one (DSS1) protocol; Signalling network layer for circuit-mode basic call control; Part 2: Specification and Description Language (SDL) diagrams

Scope

The present document specifies the stage three of circuit-mode on-demand basic telecommunication services for the
pan-European Integrated Services Digital Network (ISDN) as provided by European telecommunications operators at
the T reference point or coincident S and T reference point (as defined in ITU-T Recommendation I.411 [3]) by means
of the Digital Subscriber Signalling System No. one (DSS1). Stage three identifies the protocol procedures and
switching functions needed to support a telecommunication service (see ITU-T Recommendation I.130 [2]).
In addition, the present document specifies the protocol requirements at the T reference point where the service is
provided to the user via a private ISDN.
NOTE 1: Procedures at the T reference point, to support the access of a private ISDN to the public ISDN, are not
explicitly identified in the present document, however some procedures are applicable only to the T
reference point.
The present document does not specify the additional protocol requirements where the service is provided to the user
via a telecommunication network that is not an ISDN.
The present document is specified using the Specification and Description Language (SDL) as specified in
ITU-T Recommendation Z.100 [4].
In order to describe the point-to-multipoint operation of the protocol, the concept of a "global" process running in
parallel with a number of "individual" (dynamic) processes has been introduced. This approach, and the associated
definition of internal primitives is intended to provide a coherent description of the protocol and does not constrain
implementations. The SDL diagrams in this part, and the text of clause 5 of ETS 300 403-1 [1], together provide a
complete specification of the protocol within the scope of the present document.
A basic telecommunication service is a fundamental type of service. It forms the basis on which supplementary services
may be added.
NOTE 2: Specific requirements of individual circuit-mode basic telecommunication services are not covered in the
present document. However, ETR 018 [5] gives guidance on the use of service specific information
elements to implement individual basic telecommunication services.
The method of testing of the present document is common with that for ETS 300 403-1 [1]. Further parts of the present
document specify the method of testing and detailed application specific requirements to determine conformance based
on the present document.
The present document is applicable to equipment supporting circuit-mode on-demand basic telecommunication
services, to be attached at either side of a T reference point or coincident S and T reference point when used as an
access to the public ISDN.