Overview
SIST EN 301 656 V1.1.1:2005 is a European standard specifying the inter-exchange signalling protocol for Private Integrated Services Networks (PISN). Developed by the Slovenian Institute for Standardization (SIST), it addresses the support of Call Priority Interruption (CPI) and Call Priority Interruption Protection (CPIP) supplementary services over the Q reference point between Private Integrated Network Exchanges (PINX) within a PISN environment. This standard aligns with ISO/IEC 15992 (1998) with specific modifications for European requirements. It serves organizations implementing private telecommunication networks who require advanced call management features for reliability and prioritization.
Key Topics
- PISN and QSIG Protocol: Focused on the implementation of QSIG - the standardized network signalling protocol for private networks - promoting compatibility and interoperability among network exchanges (PINX).
- Call Priority Interruption (CPI): Defines mechanisms for temporarily interrupting ongoing lower-priority calls to allow setup or continuation of higher-priority calls, which is critical for mission-critical communication environments.
- Call Priority Interruption Protection (CPIP): Details the protective measures to safeguard certain high-priority calls from being interrupted, ensuring uninterrupted communication for key personnel or emergency functions.
- Inter-exchange Signalling: Emphasizes the standardized signalling protocol for communication between physically separate exchanges, facilitating seamless service across distributed office locations or campus environments.
- Alignment with International Standards: The standard implements modifications to ISO/IEC 15992 references, ensuring alignment and compatibility with broader international and European telecommunication standards.
Applications
SIST EN 301 656 is relevant to organizations that operate private telecommunication environments and require robust traffic management and priority handling, such as:
- Large Enterprises and Government Agencies: Ensures essential personnel maintain uninterrupted communication during high-demand periods or emergencies.
- Healthcare Facilities and Emergency Services: Enables rapid communication for critical response teams by assigning and enforcing call priorities.
- Multi-site Corporations and Campuses: Facilitates integration of branch offices or buildings through standardized PISN interconnection, upholding service quality and call management across locations.
- Service Providers and System Integrators: Systematically implement supplementary services in PISN solutions offered to clients for advanced telephony needs.
Practical benefits include improved response times during critical incidents, reduced communication downtime, and enhanced operational control over network resources.
Related Standards
Implementing SIST EN 301 656 may involve reference and interoperability with the following key standards:
- EN 300 171: Functional models and information flows for circuit-mode basic services in PISN.
- EN 300 172: Inter-exchange signalling protocol for circuit-mode basic services.
- EN 301 265: Call interception additional network feature in PISN.
- EN 301 655: Specification and functional model for CPI and CPIP supplementary services.
- ETS 300 239: Generic functional protocol for supplementary services.
- ETS 300 261: Support for Call Transfer supplementary service.
- ETS 300 357: Diversion supplementary services protocol.
- ETS 300 475-1: Reference configuration for Private Telecommunications Network Exchanges.
Using these related standards together helps ensure a unified, standards-driven approach to private network signalling, service provision, and interconnectivity.
Keywords: PISN, QSIG, Call Priority Interruption, Private Integrated Services Network, inter-exchange signalling, call prioritization, CPI, CPIP, PSS1, telephony standards, European Normes, SIST standard, ISO/IEC 15992, VPN.