SIST ETS 300 167 E1:2003

• Abstract:

  Equivalent to the parts of G.704 and G.706 relevant to 2 Mbit/s interfaces. Frame structure of 2 Mbit/s signals (basic frame & octet structured frames)including frame alignment (&CRC procedures) & use of bits in time slot 0.

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.040.20 - Transmission systems
• ICS: 35.200 - Interface and interconnection equipment
• 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 300 167 ed.1 (1993-08) - Transmission and Multiplexing (TM); Functional characteristics of 2 048 kbit/s interfaces

SIST ETS 300 167 E1:2003 specifies the synchronous frame structures and the frame alignment and Cyclic Redundancy Check (CRC) procedures for 2 048 kbit/s interfaces. It is the Slovenian standard corresponding to ETSI ETS 300 167 Edition 1, and it is aimed at making 2 Mbit/s interfaces work consistently between different vendors and operators.

What does SIST ETS 300 167 E1:2003 specify?

SIST ETS 300 167 E1:2003 covers the frame structure of 2 048 kbit/s signals, including basic frame and octet structured frames, together with CRC procedures and the use of bits in time slot 0. It is described as equivalent to the parts of G.704 and G.706 that apply to 2 Mbit/s interfaces.

The document is organized into five clauses and three annexes. Clause 1 gives the scope, Clause 2 lists normative references, Clause 3 covers definitions, Clause 4 lists abbreviations, and Clause 5 states the requirements by mapping the relevant parts of G.704 and G.706 to normative, informative, or not relevant status.

Annex	What it covers
Annex A	Examples of CRC implementations using shift registers
Annex B	Modified CRC multiframe alignment algorithm for automatic interworking between equipment with and without CRC-4 capability
Annex C	CRC-4 checksum updating procedure at intermediate path points in a message-based data-link application

What are the key requirements of SIST ETS 300 167 E1:2003?

SIST ETS 300 167 E1:2003 turns selected clauses of G.704 and G.706 into compliance requirements by marking them as normative, informative, or not relevant. In practice, that means implementers must follow the items marked N even when the underlying CCITT text is written as a recommendation or example.

• Clause 5 uses the N/I/N/R classification. This matters because it tells an implementer which parts must be built into equipment, which parts are background information, and which parts do not apply to this ETS.

• The 2 048 kbit/s frame structure in G.704 is central. Frame length, allocation of bits 1 to 8, and the CRC-4 procedure in bit 1 are treated as required items. For engineers, this is the part that fixes how the interface is framed and how receiver and transmitter behavior must match.

• Clause 5.1 covers 2 048 kbit/s interfaces carrying 64 kbit/s channels. The frame structure, the use of other 64 kbit/s channel time slots, and signalling are included. This tells system designers how channel payload and signalling occupy the frame.

• Clause 5.2 covers 2 048 kbit/s interfaces carrying n x 64 kbit/s signals. It includes both the tributary side of multiplex equipment and the multiplexed signal side. The note states that, inside a network operator's network, the time slots of an n x 64 kbit/s signal need not be contiguous, which affects multiplex planning.

• G.706 behavior for 2 048 kbit/s is also part of compliance. Loss of frame alignment, the recovery strategy, CRC multiframe alignment using bit 1, CRC bit monitoring, false frame alignment monitoring, and CRC-4 error performance monitoring are all marked normative. This is the part that governs how equipment locks onto the signal and watches for errors.

• Annex B is normative. It provides a modified CRC multiframe alignment algorithm that allows automatic interworking between equipment with and without CRC-4 capability. That is useful when older and newer equipment must operate together.

• Annex C is normative. It gives a CRC-4 checksum updating procedure for intermediate path points in a message-based data-link application. In practice, this supports correct CRC handling when a signal passes through network elements.

What terms does SIST ETS 300 167 E1:2003 use?

SIST ETS 300 167 E1:2003 uses a small set of technical terms that are important for reading the requirements.

• 2 048 kbit/s interface - The interface speed covered by the standard, commonly referred to as 2 Mbit/s.
• Basic frame - The fundamental frame format used for the 2 048 kbit/s signal.
• Octet structured frame - A frame arrangement organized around octets, which matters for how payload and overhead are placed.
• Frame alignment - The process that lets a receiver find and maintain the correct frame position.
• CRC - Cyclic Redundancy Check, the error-detection method used in the frame procedures.
• Time slot 0 - The frame position whose bits are specifically used for alignment and related functions.
• CRC-4 - The 4-bit CRC procedure referenced for 2 048 kbit/s operation and multiframe alignment.

Who uses SIST ETS 300 167 E1:2003?

SIST ETS 300 167 E1:2003 is used by equipment manufacturers, network operators, and test or verification teams working with synchronous transmission at 2 048 kbit/s. The foreword says it is intended to provide inter-vendor and inter-operator compatibility, so it is relevant wherever different suppliers' equipment must interwork.

It is also useful for engineers designing transmission and multiplexing equipment, quality managers checking interface behavior, and buyers comparing products that need to fit into the same 2 Mbit/s network environment. The document supports practical tasks such as framing design, CRC handling, and receiver alignment behavior.

Which standards are used with SIST ETS 300 167 E1:2003?

SIST ETS 300 167 E1:2003 uses two normative references.

• CCITT Recommendation G.704 (1990) - Provides the synchronous frame structures used at primary and secondary hierarchical levels, which this ETS applies to 2 048 kbit/s interfaces.
• CCITT Recommendation G.706 (1990) - Provides frame alignment and CRC procedures for basic frame structures, which this ETS adapts for 2 048 kbit/s operation.

What does the SIST ETS 300 167 E1:2003 document contain?

SIST ETS 300 167 E1:2003 contains a requirements table for G.704 and a second requirements table for G.706, both of which classify subclauses as normative, informative, or not relevant. That makes the document useful as an implementation map for what must be followed and what is only background.

The annexes add practical support material. Annex A gives shift-register examples for CRC implementation, Annex B gives the modified CRC multiframe alignment algorithm for mixed-capability equipment, and Annex C gives the checksum updating procedure for intermediate path points.

The foreword also states that conformance testing requirements are to be specified in a different ETS.

SLOVENSKI STANDARD
01-december-2003
Prenos in multipleksiranje (TM) – Funkcijske karakteristike vmesnikov s hitrostjo 2
048 kbit/s
Transmission and Multiplexing (TM); Functional characteristics of 2 048 kbit/s interfaces
Ta slovenski standard je istoveten z: ETS 300 167 Edition 1
ICS:
33.040.20 Prenosni sistem Transmission systems
35.200 Vmesniška in povezovalna Interface and interconnection
oprema equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 167
TELECOMMUNICATION August 1993
STANDARD
Source: ETSI TC-TM Reference: DE/TM-3006
ICS: 33.020, 33.040.40
Transmission, multiplexing, interfaces
Key words:
Transmission and Multiplexing (TM);
Functional characteristics
of 2 048 kbit/s interfaces
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

Page 2
ETS 300 167: 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 300 167: August 1993
Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Definitions.7
4 Abbreviations.7
5 Requirements.7
History.10

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ETS 300 167: August 1993
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ETS 300 167: August 1993
Foreword
This European Telecommunication Standard (ETS) has been produced by the Transmission and
Multiplexing (TM) Technical Committee of the European Telecommunications Standards Institute (ETSI).
This ETS aims at providing inter-vendor and inter-operator compatibility for synchronous frame structures
based on CCITT Recommendations G.704 [1] used at primary hierarchical levels and G.706 [2] on frame
alignment and Cyclic Redundancy Check (CRC) procedures relating to basic frame structures defined in
CCITT Recommendation G.704 [1].
The conformance testing requirements corresponding to the specifications contained in this ETS are to be
specified in a different ETS.
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ETS 300 167: August 1993
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ETS 300 167: August 1993
1 Scope
This ETS describes the synchronous frame structures and the frame alignment and Cyclic Redundancy
Check (CRC) procedures relevant to 2 048 kbit/s interfaces based on CCITT Recommendations G.704 [1]
and G.706 [2].
2 Normative references
This ETS incorporates by dated or 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
...