SIST ETS 300 251 E1:2003

• Abstract:

  This standard will specify the accessability of international end-to- end circuit switched 64 kbit/s traffic relations between T-reference points. The standard will not cover blocking at the user network interface nor catastrophic situations e.g. earthquakes, Floods etc.

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.040.40 - Data communication networks
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI ETS 300 251 ed.1 (1993-08) - Network Aspects (NA); Accessibility for 64 kbit/s circuit switched international end-to-end ISDN traffic relations

Overview

SIST ETS 300 251 E1:2003 defines standardized requirements for the accessibility of international end-to-end circuit-switched 64 kbit/s Integrated Services Digital Network (ISDN) traffic connections between T reference points. Developed within the Network Aspects (NA) framework, this standard ensures consistent network performance and accessibility for ISDN services across international boundaries, supporting reliable data and voice transmission for global communications.

Focusing solely on the network aspects between two T reference points, the scope specifically excludes blocking effects at the user-network interface and network interruptions caused by catastrophic events such as natural disasters. The standard provides definitions, performance criteria, and success measures to guide the design, monitoring, and evaluation of service accessibility for ISDN networks.

Key Topics

• ISDN Accessibility: The standard centers on achieving and evaluating accessibility for 64 kbit/s circuit-switched ISDN connections, a critical performance metric in digital communication networks.
• Network Performance Measures: It introduces and defines network performance (NP) indicators including Short Term Accessibility (STA), focusing on the proportion of time during which additional successful ISDN calls can be established within specified delays.
• Success Criteria: Detailed connection attempt success criteria are outlined, specifying maximum acceptable delays for activation, establishment, and connection setup phases according to referenced ISDN standards.
• Performance Objectives: The standard sets quantifiable targets, such as minimum average access probability and STA distribution thresholds, to ensure consistent accessibility over time.
• Exclusions: The document clearly states that user-network interface blocking and large-scale catastrophic events are outside its scope.

Applications

The practical value of SIST ETS 300 251 E1:2003 lies in providing a uniform framework for evaluating and improving ISDN network accessibility across multiple operators and international connections. Its main applications include:

• Network Design: Enables telecommunications operators and equipment vendors to design networks that meet minimum end-to-end accessibility requirements for 64 kbit/s ISDN traffic.
• Performance Assessment: Provides benchmarking tools to assess the accessibility of existing international ISDN links, ensuring adherence to industry-agreed levels of service availability.
• Quality of Service (QoS) Assurance: Assists network operators in maintaining high-quality service delivery by identifying and addressing network segments failing to meet accessibility criteria.
• Compliance Testing: Supports regulatory and procurement processes by supplying measurable criteria for compliance audits and network certification activities.

Related Standards

To fully implement and evaluate the requirements of SIST ETS 300 251 E1:2003, the following related standards and documents are referenced:

• Supplement No. 6 to CCITT E Series Recommendations - Establishes terminology for quality of service and network performance.
• ETR 044 - Provides reference events for performance parameters in ISDN networks.
• DE/NA-042104 - Outlines objectives for processing delays in circuit-switched ISDN connections.
• ETS 300 297 - Specifies digital section access for ISDN basic rate.
• DI/NA-042117 - Details conformance test specifications for ISDN accessibility.

Conclusion

SIST ETS 300 251 E1:2003 serves as an authoritative guide for ISDN network accessibility, supporting international interoperability and ensuring high-quality digital communication. By adhering to this standard, network operators can enhance reliability, meet customer expectations, and align with global best practices for ISDN service provision.

SLOVENSKI STANDARD
01-december-2003
Omrežni vidiki (NA) – Dostopnost mednarodnih vodovno komutiranih prometnih
povezav konec-konec za hitrosti 64 kbit/s v ISDN
Network Aspects (NA); Accessibility for 64 kbit/s circuit switched international end-to-end
ISDN traffic relations
Ta slovenski standard je istoveten z: ETS 300 251 Edition 1
ICS:
33.040.40 Podatkovna komunikacijska Data communication
omrežja networks
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 251
TELECOMMUNICATION August 1993
STANDARD
Source: ETSI TC-NA Reference: DE/NA-042106
ICS: 33.080
ISDN, access
Key words:
Network Aspects (NA);
Accessibility for 64 kbit/s circuit switched
international end-to-end ISDN traffic relations
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
F-06921 Sophia Antipolis CEDEX - FRANCE
Postal address:
650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Office address:
c=fr, a=atlas, p=etsi, s=secretariat - [e-mail]
X.400: Internet:
Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1993. All rights reserved.
New presentation - see History box

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ETS 300 251: August 1993
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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ETS 300 251: August 1993
Contents
Foreword.5
1 Scope .7
2 Normative references .7
3 Definitions. 7
4 Symbols and abbreviations.8
5 Explicit definition for a measure for accessibility performance .8
5.1 Introduction.8
5.2 Principles and definitions.8
6 Requirements.9
7 Success criteria for connection attempts. 10
8 Evaluation of the NP measure for accessibility . 11
History. 13

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ETS 300 251: August 1993
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ETS 300 251: August 1993
Foreword
This European Telecommunication Standard (ETS) has been prepared by the Network Aspects (NA)
Technical Committee of the European Telecommunications Standards Institute (ETSI).
This ETS specifies the accessibility of international end-to-end circuit-switched 64 kbit/s Integrated
Services Digital Network (ISDN) traffic relations between T reference points.

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ETS 300 251: August 1993
Blank page
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ETS 300 251: August 1993
1 Scope
This European Telecommunication Standard (ETS) specifies the accessibility of international end-to-end
circuit-switched 64 kbit/s Integrated Services Digital Network (ISDN) traffic relations between T reference
points.
This ETS does not cover blocking at the user-network interface nor catastrophic situations, e.g. earth
quakes, floods, etc.
NOTE: A corresponding compliance ETS is planned for September 1994. Until the document is
available, this ETS may be used for design purposes.
2 Normative references
This ETS incorporates by dated and undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply
to this ETS only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referred to applies.
[1] Supplement No. 6 to CCITT E series Recommendations: "Terms and definitions
of Quality of Service, Network Performance, Dependability and Trafficability
studies".
[2] ETR 044: "Network Aspects (NA); Reference events for network performance
parameters in an ISDN".
[3] DE/NA-042104: "Network performance objectives for circuit-switched connection
processing delays in an ISDN".
[4] ETS 300 297: "Integrated Services Digital Network (ISDN); Access Digital
Section for ISDN basic rate".
[5] DI/NA-042117: "Network Aspects (NA); Accessibility for 64 kbit/s
circuit-switched international end-to-end ISDN traffic relations Conformance test
specification".
3 Definitions
For the purpose of this ETS, the following definitions apply:
Accessibility performance: the ability of a network to provide a connection within a specified delay when
a correct request is received from the user at the T interface.
NOTE: The request includes activation of layer 1.
Accessibility: a measure for accessibility performance. The explicit definition of the measure is given in
Clause 5 of this ETS.
Measure: a function or quantity used to describe a random variable or a random process (definition
number 3011 in Supplement No. 6 to CCITT E series Recommendations [1]).
Short Term Accessibility (STA): the explicit definition of the STA is given in Clause 5 of this ETS.

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ETS 300 251: August 1993
4 Symbols and abbreviations
For the purpose of this ETS, the following symbols and abbreviations are used:
MPT1 Measurement Point 1
NP Network Performance
STA Short Term Accessibility
T Time interval over which the random variable STA is defined
a
T interface at reference point T
SABME Set Asynchronous Balanced Mode Extended
UA Unnumbered Acknowledgement
5 Explicit definition for a measure for accessibility performance
5.1 Introduction
A Network Performance (NP) measure for accessibility performance should be as simple and easy to
evaluate as possible. On the other hand, as the quality of service measure for accessibility performance
depends mainly on the corresponding NP measure of the used network, a NP measure for accessibility
performance has to characterise, as accurately as possible, the aspects which are important for the user.
These requirements are conflicting and there
...