Overview
SIST EN 301 258 V1.1.1:2005 defines the stage 3 (protocol implementation) of the Recall supplementary service in Private Integrated Services Networks (PISN). This European standard, based on and modifying ISO/IEC 15052 (1997), sets out the inter-exchange signalling protocol essential for supporting the Recall service between network exchanges via the QSIG protocol-the Private Integrated Signalling System No. 1 (PSS1).
The Recall supplementary service enables users in a PISN to initiate a recall to another user after the original call is released, improving the efficiency and usability of private telephone networks. The specification adheres to the Open Systems Interconnection (OSI) model and leverages ISDN concepts for enhanced integration and interoperability within private and virtual private networks.
Key Topics
- Inter-exchange Signalling: Specifies the protocol for communication between PISN exchanges, ensuring standardised message flows and procedures for Recall operations.
- Recall Supplementary Service: Details how the service is triggered and managed across multiple network nodes, supporting seamless recall functionality.
- QSIG Protocol (PSS1): Describes the use and adaptation of QSIG at the ‘Q reference point’, facilitating vendor-neutral signalling between different system components.
- Protocol Stages: Focuses on stage 3, which covers the implementation of service features through precise protocol elements and procedures.
- Compatibility and Modifications: Includes normative references to other essential standards, clarifying modifications applied in this European standard for consistent application across networks.
Applications
The Recall supplementary service, as defined in SIST EN 301 258 V1.1.1:2005, is crucial in the following scenarios:
- Enterprise Telephony Networks: Supports business environments where users frequently need to reconnect after call releases, thereby increasing communication productivity.
- Virtual Private Networks (VPN): Enables consistent user experience and robust feature support in distributed organisation networks interconnected by PISN.
- Interoperability Between Multi-vendor Systems: Eases integration challenges by providing a common protocol reference for different manufacturers’ equipment, aiding seamless recall features across complex telephony infrastructures.
- Advanced Telecommunication Services: Forms a core requirement in environments demanding supplementary services beyond basic voice, such as call hold, transfer, diversion, and recall, ensuring competitive and feature-rich telephony solutions.
Related Standards
For a well-rounded telecommunication environment and the correct application of the Recall service protocol, it is recommended to consult the following related standards:
- EN 300 171: PISN specification, functional models, and information flows.
- EN 300 172: PISN inter-exchange signalling protocol for circuit-mode basic services.
- ETS 300 239: Generic functional protocol for the support of supplementary services.
- ETS 300 261: Protocol specifications for call transfer supplementary services.
- EN 301 257: Specifies the Recall supplementary service functional models and flows.
- EN 301 265: Call interception features for PISN.
- ETS 300 387: Methods for specifying basic and supplementary services in Private Telecommunication Networks.
Understanding and implementing these standards in conjunction with SIST EN 301 258 V1.1.1:2005 ensures comprehensive support for advanced telephony features, maximising the performance and efficiency of private integrated services networks.
By applying the protocols and frameworks set out in this standard, organisations can deliver reliable Recall services, guarantee network interoperability, and maintain compliance with European telecommunication requirements.