This International Standard is a part of the functional requirements for the Private Integrated Services Network (PISN) and defines the functions and procedures that are required by Private Integrated Services Network exchanges (PINXs) and the intervening network (IVN) in order to establish Inter-PINX Connections (IPC). The IPC is used for the transfer of signalling and user information between PINXs.
The Private Signalling System No.1 (PSS1) as defined in ISO/IEC 11572 and 11574 defines the signalling procedures and protocol for call control between PINXs at the Q reference point. These procedures are independent of the types of IVNs, called scenarios used to interconnect the PINXs. ISO/IEC TR14475 describes the use of various types of IVNs which provide the interconnections of PINXs.
In order to connect a PINX to another PINX, mapping functions are required to adapt the specific interfaces at the C reference point to the application at the Q reference point. As such, mapping functions provide for physical adaptation to the interface at the C reference point. Mapping functions also provide for the mapping of user channels and signalling information at the Q reference point to the appropriate channels or time-slots at the C reference point. The C and Q reference points are defined in ISO/IEC 11579-1.
The types of interfaces at the C reference point covered by this International Standard are:
 1544 kbit/s unstructured digital leased line
 1544 kbit/s structured digital leased line
 2048 kbit/s unstructured digital leased line
 2048 kbit/s structured digital leased line
 64 kbit/s unrestricted digital leased line
 1544 kbit/s ISDN Primary Rate user-network layer 1 interface
 2048 kbit/s ISDN Primary Rate user-network layer 1 interface
 ISDN Basic Rate user-network layer 1 interface
At the Q reference point the mappings provide a 64 kbit/s service for user channels and a packet mode service for the signalling channel. The applied mapping is a static mapping, i.e. there is a fixed relationship between user and signalling channels at the Q reference point and the timeslots of the interface at the C reference point. Any changes are subject to administrative actions.
This International Standard specifies PINX mapping functions between the Q reference point and the C reference point for IVNs which provide either dedicated or semi-permanent, non-user activation, circuit-mode IPCs. The dedicated IPC is the connection permanently established, usually for the duration of a contractual period. The semi-permanent IPC is the connection whose resources are reserved for specified times during a contractual period. The semi-permanent IPC is established by management control with or without user activations. In this International Standard, the semi-permanent IPC established by management control with user activation is outside the scope.
The IVN can be a dedicated physical link, dedicated transmission system or a cross connect system, or semi-permanent connection system. IVNs which include inverse mulitlexer techniques (e.g. channel aggregation in accordance with ISO/IEC 13871) are covered by this International Standard so far as they support one of the interfaces listed above.
This International Standard also specifies mapping information. At both sides of the PINX, mapping information is required to administer the scenarios.
This International Standard is applicable to PINXs which can be interconnected to form a Private Integrated Services Network (PISN) and which support signalling protocols at the Q reference point.