SIST EN 301 820 V1.2.1:2005

SIST EN 301 820 V1.2.1:2005 is the Slovenian adoption of ETSI EN 301 820, and it endorses ISO/IEC 15772 (2003) with ETSI modifications. It specifies the inter-exchange signalling protocol for the Common information Additional Network Feature (ANF) in Private Integrated Services Network (PISN), for use at the Q reference point and within the PSS1 protocol family, informally known as QSIG.

What does SIST EN 301 820 V1.2.1:2005 specify?

SIST EN 301 820 V1.2.1:2005 specifies a signalling protocol for PISN inter-exchange communication in support of the Common information ANF. The document is an endorsement of ISO/IEC 15772 (2003), so its main role is to adopt that International Standard in ETSI/SIST form and apply a set of European modifications.

The document is organized around a foreword, national transposition dates, an endorsement notice, clause 3 on references, and a history block. In practice, that means the reader uses it as the authoritative European version of the ISO text, together with the ETSI reference updates listed in the modifications.

What are the key requirements of SIST EN 301 820 V1.2.1:2005?

SIST EN 301 820 V1.2.1:2005 applies the elements of ISO/IEC 15772 (2003) with specific modifications. The most important technical point is that the signalling defined here is the protocol used at the Q reference point to support the Common information ANF in PISN.

How the document handles references

Clause 3 replaces the generic introductory paragraph on references with ETSI wording that distinguishes between specific and non-specific references. For a user, this tells you whether to lock to a dated edition or follow the latest available version.

Clause 3 also adds a set of normative ETSI references. This matters because the protocol text is not standalone - implementers are expected to use the linked ETSI standards for the services and functional models that the protocol depends on.

How ISO/IEC references are mapped

Throughout the text of ISO/IEC 15772, the standard replaces ISO/IEC reference names with ETSI equivalents. This is a practical interoperability rule: when the original ISO text points to another standard, this European version points to the ETSI document that should be used in PISN work.

How the wording is adapted

The document replaces the phrase “this International Standard” with “the present document.” This is a small but important editorial change, because it makes the adopted ETSI version self-contained and avoids ambiguity about which text governs.

What the foreword establishes

The foreword places the standard in the PISN series, says the series uses ISDN concepts developed by ITU-T, and states that it conforms to the OSI framework. For a reader, that shows the protocol is part of a broader signalling architecture rather than an isolated feature definition.

What terms does SIST EN 301 820 V1.2.1:2005 define?

• PISN - Private Integrated Services Network, the network type for which the signalling protocol is intended.
• ANF - Additional Network Feature, an added service capability beyond the basic network functions.
• ISDN - Integrated Services Digital Network, the concept base used by the PISN series.
• OSI - Open Systems Interconnection, the framework the series follows.
• PSS1 - The protocol family that carries the inter-exchange signalling defined here.
• QSIG - The informal name used for the PSS1 protocol family.
• Q reference point - The interface point where this signalling is applied between PISN exchanges.

Who uses SIST EN 301 820 V1.2.1:2005?

SIST EN 301 820 V1.2.1:2005 is used by telecommunications engineers, PISN equipment vendors, protocol implementers, and interoperability test teams. It is also relevant to buyers and quality managers who need to specify signalling support for systems that use the Common information ANF. In practice, it helps when designing, integrating, testing, or procuring PISN/QSIG-related exchange equipment.

What changed in SIST EN 301 820 V1.2.1:2005 from the previous edition?

This version endorses ISO/IEC 15772 (2003) and applies ETSI modifications. The stated changes are the rewritten reference clause, the insertion of ETSI normative references, the replacement of several ISO/IEC reference documents with ETSI standards, and the wording change from “this International Standard” to “the present document.” The history block also records an earlier publication as V1.1.1 and the current publication as V1.2.1.

Which standards are used with SIST EN 301 820 V1.2.1:2005?

What does the SIST EN 301 820 V1.2.1:2005 document contain?

The document contains the endorsement notice for ISO/IEC 15772 (2003), the ETSI editorial modifications, and the normative reference updates. It also includes transposition dates and a short publication history. The technically important content is the mapping from ISO/IEC references to ETSI references, which governs how the protocol is read and implemented in practice.