Overview
SIST EN 301 919 V1.1.1:2005 defines the inter-exchange signalling protocol for the Private Integrated Services Network (PISN) to support the single step call transfer supplementary service. Developed by SIST and based on the modified ISO/IEC 19460:2003 standard, this document specifies how a user (user A) can transfer an active call with user B to a third party (user C), even if user A does not have a call established with user C before initiating the transfer. This functionality enhances the flexibility and efficiency of private telecommunication networks by enabling seamless call management across PISN nodes.
This standard forms part of the broader PSS1 protocol suite, commonly known as QSIG, which is a widely recognized protocol for signalling in PISN environments. The QSIG protocol ensures interoperability and standardized communication between exchanges within private networks using ISDN (Integrated Services Digital Network) principles.
Key Topics
- Single Step Call Transfer: Specifies the procedure and signalling requirements for transferring a call in a single action. User A can actively connect user B and user C and then drop out of the call, streamlining business communications.
- Inter-exchange Signalling Protocol: Details the protocol used at the "Q reference point" between two PISN exchanges (PINXs), ensuring interoperability for supplementary services.
- PSS1 (QSIG) Supplementary Service: The standard belongs to the suite of PSS1 protocols, supporting advanced features like call transfer, call diversion, advice of charge, and name identification within private networks.
- Reference Model: Conforms to the OSI (Open Systems Interconnection) and ISDN architectural models as developed by ITU-T and described in ISO/IEC standards.
- Compatibility and Endorsement: Endorses and modifies ISO/IEC 19460, includes updates and references to related ETSI and ISO/IEC standards for addressing, basic call, call diversion, and other supplementary services.
Applications
The practical value of SIST EN 301 919 V1.1.1:2005 is in its wide application within corporate and organizational telecommunication infrastructures:
- Enterprise PBX Systems: Enables businesses with a Private Integrated Services Network to offer efficient call transfer capabilities, reducing manual intervention and allowing employees to quickly redirect calls.
- Interconnected Office Branches: Facilitates seamless call routing and management between offices connected by PISNs, improving internal communications.
- Customer Service Centers: Enhances customer experience by allowing operators to transfer calls to the appropriate expert without dropping or redialing.
- ISDN-based Environments: Provides support for organizations transitioning to or maintaining ISDN-based backbone networks, offering robust supplementary services.
These applications are essential for organizations seeking reliable, scalable, and standard-conformant telephony services.
Related Standards
To ensure comprehensive support for PISN environments, this standard references and works in conjunction with other key standards:
- EN 300 189: PISN Addressing [ISO/IEC 11571, modified]
- EN 300 172: Circuit-mode Basic Services [ISO/IEC 11572, modified]
- EN 300 171: Bearer Services Information Flows [ISO/IEC 11574, modified]
- EN 300 239: Generic Functional Protocol for Supplementary Services [ISO/IEC 11582, modified]
- EN 300 238: Name Identification Supplementary Service [ISO/IEC 13868, modified]
- EN 300 261: Call Transfer Supplementary Service [ISO/IEC 13869, modified]
- EN 300 171/EN 301 918: Specification and information flows for single step call transfer [ISO/IEC 19459, modified]
For full interoperability and feature coverage in private telephone networks, adherence to these related standards is recommended.
Keywords: Private Integrated Services Network, PISN, single step call transfer, supplementary service, QSIG, inter-exchange signalling protocol, ISDN, ETSI, EN 301 919, ISO/IEC 19460.
