ETSI ETS 300 233 ed.1 (1994-05)

Integrated Services Digital Network (ISDN); Access digital section for ISDN primary rate

DE/TM-03003

Digitalno omrežje z integriranimi storitvami (ISDN) – Dostopovni digitalni oddelek za primarne funkcije ISDN

General Information

• Status: Published
• Publication Date: 09-May-1994
• Technical Committee: TM 3 - Interfaces, architecture and functional requirements of transport netw
• Current Stage: 12 - Completion
• Due Date: 23-Feb-1994
• Completion Date: 10-May-1994
• Ref Project: SIST ETS 300 233 E1:2003 - Integrated Services Digital Network (ISDN); Access digital section for ISDN primary rate

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 233 E1:2003
01-december-2003
Digitalno omrežje z integriranimi storitvami (ISDN) – Dostopovni digitalni oddelek
za primarne funkcije ISDN
Integrated Services Digital Network (ISDN); Access digital section for ISDN primary rate
Ta slovenski standard je istoveten z: ETS 300 233 Edition 1
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
SIST ETS 300 233 E1:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 233 E1:2003
EUROPEAN ETS 300 233
TELECOMMUNICATION May 1994
STANDARD
Source: ETSI TC-TM Reference: DE/TM-03003
ICS: 33.020
Transmission, multiplexing, ISDN
Key words:
Integrated Services Digital Network (ISDN);
Access digital section for ISDN primary rate
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 1994. All rights reserved.
New presentation - see History box

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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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Contents
Foreword.5
1 Scope .7
2 Normative references .7
3 Definitions and abbreviations.8
3.1 Definitions.8
3.2 Abbreviations.8
4 Configuration and application.9
4.1 Configuration .9
4.2 Application.11
4.3 Modelling and relationship between the access digital section and the ET.11
5 Functions.13
5.1 B-channel .13
5.2 H0-channel .13
5.3 H1-channel .13
5.4 D-channel .13
5.5 Bit timing .14
5.6 Octet timing.14
5.7 Frame alignment .14
5.8 CRC-4 procedure.14
5.9 M-channel.14
5.10 Power feeding .14
5.11 Operation and maintenance of the access digital section.14
6 Signal transfer delay.14
7 Jitter .15
7.1 Output/input jitter at T reference point.15
7.2 Jitter at the V3 reference point.15
8 Operation and maintenance.15
8.1 Control facilities .15
8.1.1 Loopbacks.15
8.1.1.1 Loopback implementation.15
8.1.1.2 Loopback procedure.15
8.2 Monitoring .15
8.2.1 Functions.15
8.2.2 Defect conditions and consequent actions .16
8.2.2.1 Detection of defect conditions.16
8.2.2.2 Definition of defect indication signals .16
8.2.2.3 Detection of defect indication signals.17
8.2.2.4 Definition of detection algorithms.17
8.2.2.5 Consequent actions .18
8.3 Error performance monitoring.18
9 Operation and maintenance procedures.18
9.1 Partitioning of functions.18
9.2 Definitions of signals at the T reference point .20
9.3 Definition of signals at the V3 reference point.20
9.4 Definition of ET layer 1 state machine.24

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9.5 Definition of DS state machine.24
9.5.1 DS states .24
9.5.2 DS state transition table.24
9.5.2.1 Assumptions.25
9.5.2.2 Classification of DS states.25
9.5.2.3 Definition of notations.25
9.5.2.4 NOTES to DS state tables 5a to 5j.55
Annex A (normative): System management requirements.56
A.1 Introduction.56
A.2 System management requirements .56
A.2.1 General .56
A.2.2 Error indications .56
A.2.3 Loopback operations .56
A.2.4 Information to be sent in the D-channel during loopback operation.57
A.2.5 Configuration control.57
A.3 Handling of CRC error information in the ET.57
A.4 Definition of ET layer 1 state machine .57
A.4.1 ET layer 1 states.57
A.4.2 PH and MPH primitives .57
A.4.2.1 The repertoire of PH and MPH primitives.57
A.4.2.2 Repertoire of MPH primitives.57
A.4.3 ET layer 1 state transition table.58
A.4.3.1 Definition of notations.58
A.4.3.2 Classification of ET states.59
Annex B (normative): Combined ET and LT functions.73
Annex C (normative): Conformance testing .73
Annex D (informative): Bibliography.73
Annex E (informative): NT1 functions with 2 048 kbit/s and Option 2.74
History .75

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Foreword
This European Telecommunication Standard (ETS) has been produced by the Transmission and
Multiplexing (TM) Technical Committee of the European Telecommunications Standards Institute (ETSI).
Annexes A to C of this ETS are normative whereas Annexes D and E are informative.
NOTE: ITU-T Recommendation G.962 (1993) is based upon this ETS.

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1 Scope
This ETS specifies the characteristics of an access digital section for the Integrated Services Digital
Network (ISDN) primary rate access between the user-network interface (at the T reference point, defined
in ETS 300 011 [1]) and the local exchange (at the V.3 reference point, defined in CCITT Recommendation
Q.512 [4]) supporting the primary rate interface channel structure defined in CCITT Recommendation
I.412 [3] and ETS 300 011 [1] and the additional functions required for operation and maintenance of the
access digital section according to ETR 001 [2], Option 2.
NOTE: ITU-T Recommendation G.962 (1993) is based upon this ETS.
The requirements of this ETS satisfy network performance requirements of CCITT Recommendations
G.821 [5] on error performance as well as CCITT Recommendations G.801 and I.350 with regard to
availability.
Annex A (normative) to this ETS specifies requirements for interworking between the Primary Rate Access
Digital Section (DS) and the Exchange Termination (ET) and the definition of the ET layer 1 state machine
which are outside the scope of this ETS but which are nevertheless important.
Annex B (normative) specifies a modification of the requirements when Line Termination (LT) and ET
functions are combined in one unit.
Annex C (normative), to be provided, will specify the requirements for conformance testing.
This ETS does not specify the requirements of the digital transmission system used within the access
digital section.
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 latest edition of the
publication referred to applies.
[1] ETS 300 011 (1992): "Integrated Services Digital Network (ISDN); Primary rate
user-network interface; layer 1 specification and test principles".
[2] ETR 001: "Integrated Services Digital Network (ISDN); Customer access
maintenance".
[3] CCITT Recommendation I.412 (1988): "ISDN user-network interfaces - Interface
structures and access capabilities".
[4] CCITT Recommendation Q.512 (1988): "Exchange interfaces for subscriber
access".
[5] CCITT Recommendation G.821 (1988): "Error performance of an international
digital connection forming part of an integrated services digital network".
[6] CCITT Recommendation G.823 (1988): "The control of jitter and wander within
digital networks which are based on the 2048 kbit/s hierarchy".
[7] CCITT Recommendation G.706 (1988): "Frame alignment and cyclic redundancy
check (CRC) procedures relating to basic frame structures defined in
Recommendation G.704".
[8] CCITT Recommendation G.703 (1988): "Physical/electrical characteristics of
hierarchical digital interfaces".

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[9] CCITT Recommendation G.704 (1988): "Synchronous frame structures used at
primary and secondary hierarchical levels".
[10] CCITT Recommendation Q.940 (1988): "ISDN user-network interface protocol
for management - general aspects".
[11] CCITT Recommendation I.411 (1988): "ISDN user-network interfaces -
Reference configuration".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this ETS, unless otherwise indicated, the term TE is used to indicate terminating layer
1 aspects of TE1, TA and NT2 functional groups.
When the term TE indicates terminating layer 1 aspects of TE1, then according to figure 2 of CCITT
Recommendation I.411 [11], the S and T reference points coincide.
In this ETS references to LT only concern the LT inside the access digital section.
3.2 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
AIS Alarm Indication Signal
AUXP AUXiliary Pattern
CRC-4 Cyclic Redundancy Check
DS Primary Rate Access Digital Section
ET Exchange Termination
ETS European Telecommunication Standard
ETSI European Telecommunications Standards Institute
FC4 Failure Condition
FE Function Element
μs micro second
HDLC High Level Data Link Control
ISDN Integrated Services Digital Network
LFA Loss of Frame Alignment
LOS Loss of Signal
LT Line Termination
NF Normal Frame
NOF Normal Operational Frames
NT Network Termination

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PH Packet Handler
RAI Remote Alarm Indication
SIG Signal between LT and NT1
TE Terminal Equipment
4 Configuration and application
4.1 Configuration
Figure 1 below shows the boundaries of the access digital section in relation to the digital transmission
system definition.
The concept of the access digital section is used in order to allow a functional and procedural description
and a definition of the network requirements.
The concept of a digital transmission system is used in order to describe the characteristics of an
implementation, using a specific medium, in support of the access digital section.
            Digital transmission
                system
             ‡<˜˜˜˜˜˜˜˜˜˜˜˜>‡
  �˜˜˜˜˜˜˜¿   �˜˜˜˜˜˜·  (NOTE 2) ˆ˜˜˜˜˜˜¿    �˜˜˜˜˜˜¿
  ‡    ‡   ‡   ‡       ‡   ‡    ‡   ‡
  ‡ TE  ˆ˜˜˜˜´˜· NT1 ˆ˜˜˜˜˜˜˜˜˜˜˜˜˜˜· LT ˆ˜˜˜´˜˜˜· ET ‡
  ‡    ‡  ‡ ‡   ‡       ‡   ‡  ‡  ‡   ‡
  ‡    ‡   ‡   ‡       ‡   ‡    ‡   ‡
  �˜˜˜˜˜˜˜�  T �˜˜˜˜˜˜�       �˜˜˜˜˜˜� V3  �˜˜˜˜˜˜�
     reference point          reference point
         ‡   Primary Rate Access     ‡
         ‡    Digital Section (DS)   ‡
         ‡<˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜>‡
         ‡                 ‡

NOTE 1: From a functional point of view the information transferred via the reference points T and V3 are
different and, therefore, the digital section is not symmetrical.
NOTE 2: Digital transmission system refers to either a line system using metallic media or optical fibres or
to a radio system.
Figure 1: Access digital section and transmission system boundaries

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        T    Primary Rate Access Digital Section (DS)  V3
        ‡<˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜>‡
        ‡         (NOTE 1)             ‡
     �˜˜˜¿ ‡ �˜˜˜¿                    �˜˜˜¿ ‡ �˜˜˜˜¿
     ‡  ‡ ‡ ‡  ‡                    ‡  ‡ ‡ ‡  ‡
     ‡NT2ˆ˜¯˜·NT1ˆ˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜·LT ˆ˜¯˜·  ‡
     ‡  ‡ ‡ ‡  ‡                    ‡  ‡ ‡ ‡  ‡
     �˜˜˜� ‡ �˜˜˜�                    �˜˜˜� ‡ ‡  ‡
                                   ‡  ‡
        T       Digital access link         V3’‡  ‡
        ‡<˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜>‡ ‡  ‡
        ‡   Access  V3                 ‡ ‡  ‡
        ‡digital section ‡ One first order digital section ‡ ‡  ‡
        ‡<˜˜˜˜˜˜˜˜˜˜˜˜˜˜>‡<˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜>‡ ‡  ‡
     �˜˜˜¿ ‡ �˜˜˜¿  �˜˜˜¿ ‡ �˜˜˜˜¿          �˜˜˜˜¿ ‡ ‡  ‡
     ‡  ‡ ‡ ‡  ‡  ‡  ‡ ‡ ‡Line‡          ‡Line‡ ‡ ‡  ‡
     ‡NT2ˆ˜¯˜·NT1ˆ˜˜˜˜·LT ˆ˜¯˜·  ˆ˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜·  ˆ˜¯˜·  ‡
     ‡  ‡ ‡ ‡  ‡  ‡  ‡ ‡ ‡term‡          ‡term‡ ‡ ‡  ‡
     �˜˜˜� ‡ �˜˜˜�  �˜˜˜� ‡ �˜˜˜˜�          �˜˜˜˜� ‡ ‡  ‡
        ‡  (NOTE 1)  ‡                 ‡ ‡  ‡
                                   ‡  ‡
        T                         V3’‡  ‡
        ‡         Digital access link       ‡ ‡  ‡
        ‡<˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜>‡ ‡ ET ‡
        ‡        V3                 ‡ ‡  ‡
        ‡  Access   ‡     ‡ Digital link ‡     ‡ ‡  ‡
        ‡digital section ‡     ‡  G.921   ‡     ‡ ‡  ‡
        ‡<˜˜˜˜˜˜˜˜˜˜˜˜˜˜>‡     ‡<˜˜˜˜˜˜˜˜˜˜˜˜>‡     ‡ ‡  ‡
        ‡   (NOTE 1)  ‡     ‡  (NOTE 2) ‡     ‡ ‡  ‡
     �˜˜˜¿ ‡ �˜˜˜¿  �˜˜˜¿ ‡ �˜˜˜˜˜¿ ‡       ‡ �˜˜˜˜˜¿ ‡ ‡  ‡
     ‡  ‡ ‡ ‡  ‡  ‡  ‡ ‡ ‡   ‡ ‡       ‡ ‡   ‡ ‡ ‡  ‡
     ‡NT2ˆ˜¯˜·NT1ˆ˜˜˜˜·LT ˆ˜¯˜·   ‡ ‡       ‡ ‡   ‡ ‡ ‡  ‡
     ‡  ‡ ‡ ‡  ‡  ‡  ‡ ‡ ‡   ‡ ‡�˜˜˜˜¿ �˜˜˜˜¿‡ ‡   ˆ˜¯˜·  ‡
     �˜˜˜� ‡ �˜˜˜�  �˜˜˜� ‡ ‡   ‡ ‡‡Line‡ ‡Line‡‡ ‡   ‡ ‡ ‡  ‡
        ‡        ‡ ‡ Mux ˆ˜¯·  ˆ˜˜·  ˆ¯˜· MUX ‡ ‡ ‡  ‡
     �˜˜˜¿ ‡ �˜˜˜¿  �˜˜˜¿ ‡ ‡   ‡ ‡‡term‡ ‡term‡‡ ‡   ‡ ‡ ‡  ‡
     ‡  ‡ ‡ ‡  ‡  ‡  ‡ ‡ ‡   ‡ ‡�˜˜˜˜� �˜˜˜˜�‡ ‡   ‡ ‡ ‡  ‡
     ‡NT2ˆ˜¯˜·NT1ˆ˜˜˜˜·LT ˆ˜¯˜·   ‡         ‡   ˆ˜¯˜·  ‡
     ‡  ‡ ‡ ‡  ‡  ‡  ‡ ‡ ‡   ‡         ‡   ‡ ‡ ‡  ‡
     �˜˜˜� ‡ �˜˜˜�  �˜˜˜� ‡ ‡   ‡         ‡   ‡ ‡ ‡  ‡
        ‡        ‡ �˜˜˜˜˜�         �˜˜˜˜˜� ‡ �˜˜˜˜�
                                (NOTE 3)
NOTE 1: The access digital sections may include one or more regenerators.
NOTE 2: Multiple applications of digital links and multiplexors may be possible, but see also subclause
7.2 "Jitter at the V3 reference point".
NOTE 3: In the case of remote access, the digital access link is terminated at the ET by a V3' reference
point which is functionally and electrically identical with the V3 reference point in the case of the
direct access.
NOTE 4: The Line Terminations (LTs) forming part of the first order digital section or the digital link are
outside the scope of this ETS.
Figure 2: Examples of equipment configurations in the ISDN primary rate access

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4.2 Application
The Primary Rate Access Digital Section (DS) may be applied as given in figure 2 for:
- direct access to the local exchange;
- remote access via one first order digital section or via higher order multiplex equipment forming a
digital access link to the local exchange.
4.3 Modelling and relationship between the access digital section and the ET
The general model, as shown in figure 3, depicts the whole ISDN customer access layer 1 and adjacent
entities. It also provides the basis to describe the functions performed by the access digital section and
those performed by TE, ET and system management and how various functions are grouped. In particular,
according to this model, the maintenance functions specified in this ETS are not confined to functions
performed by the access digital section but include functions associated with ET layer 1.
This model includes primitive procedures between ET layer 1, ET layer 2 and system management:
a) ETS 300 011 [1] and CCITT Recommendations Q.920/Q.921 interactions between ET layer 1 and
ET layer 2 and system management based on Packet Handler (PH) and MPH primitives,
respectively, as defined in ETS 300 011 [1]. These interactions are for the support of functions
specified in CCITT Recommendations Q.920 and Q.921;
b) interactions between ET layer 1 and system management for the support of functions associated
with the access digital section, based on MPH primitives.
The primitive procedures within TE comply with the specification according to ETS 300 011 [1].
This model does not constrain layer 1 arrangements between LT and NT1, nor the digital transmission
system technology.

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PH-primitves
PH-primitves
according to
according to
ETS 300 011[1]
B-channels
B-channels
ETS 300 011 [1]
Function MPH-Primitives
SIGs
MPH-Primitives
SIGs
Elements according to
(NOTE 2)
(NOTE 2)
according to
(NOTE 2) ETS 300 011 [1]
 ET
 TE
ETS 300 011[1]
layer 1
layer 1
LT
NT1
Digital
MPH-Primitives
transmission
T
V3 associated with
system
(NOTE 1)
line system
Access digital section
NOTE 1: The digital transmission system refers to either a digital system using a metallic pair of wires, optical fibre or radio system.
NOTE 2: SIG, FE and primitives refer to an exchange of information. It does not imply any specific coding nor implementation. Some of these functions may be terminated
in the LT and do not pass the digital transmission system.
NOTE 3: The term system management corresponds to both system management and layer management as defined in CCITT Recommendation Q.940 [10].
Figure 3: General model of ISDN customer access layer 1 and adjacent entities
System management (NOTE 3)
TE
layer 2
ET
layer 2
System management (NOTE 3)

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5 Functions
Figure 4 below shows the functions which shall be supported by the Primary Rate Access Digital Section.
               Primary Rate Access
    T reference point   Digital Section    V3 reference point
             �------------¿
      <-----------> ‡B-, H0- or H1-channels ‡ <----------->
             ˆ------------·
      <-----------> ‡D-channel        ‡ <----------->
             ˆ------------·
      <-----------> ‡Bit timing       ‡ <----------->
             ˆ------------·
      <-----------> ‡Octet timing      ‡ <----------->
             ˆ------------·
      <-----------> ‡Frame alignment     ‡ <----------->
             ˆ------------·
      <-----------> ‡CRC procedures     ‡ <----------->
             ˆ------------·
      <-----------> ‡M-channel        ‡ <----------->
             ˆ------------·
      -----------> ‡Power feeding (NOTE)  ‡
             ˆ------------·
      <-----------> ‡Operation & Maintenance ‡ <----------->
             �------------�
NOTE: This power-feed-function is optional and depends on the transmission medium used. Only the
NT1 may be powered from the interface at the T reference point (see ETS 300 011 [1]).
Figure 4: Functions supported in the access digital section
For each direction of transmission the following functions shall be provided:
- 30 timeslots at 64 kbit/s (numbered 1 to 15 and 17 to 31) for the transport of any appropriate
allocation of the B-, H0- and H1-channels;
- 1 timeslot at 64 kbit/s (numbered 16) for the transport of a D-channel;
- 1 timeslot at 64 kbit/s (numbered 0) for frame alignment, and to follow the procedures for multiframe
alignment, CRC-4 procedures and maintenance.
5.1 B-channel
This function provides for the bi-directional transmission of up to 30 independent B-channels, each having a
bit rate of 64 kbit/s as defined in CCITT Recommendation I.412 [3].
5.2 H0-channel
This function provides for the bi-directional transmission of up to 5 independent H0-channels, each having a
bit rate of 384 kbit/s as defined in CCITT Recommendation I.412 [3].
5.3 H1-channel
This function provides for the bi-directional transmission of one H1-channel having a bit rate of 1 920 kbit/s
as defined in CCITT Recommendation I.412 [3].
5.4 D-channel
This function provides for the bi-directional transmission of one D-channel at a bit rate of 64 kbit/s as
defined in CCITT Recommendation I.412 [3].

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5.5 Bit timing
This function provides bit (signal element) timing to enable the TE, the access digital section or the ET to
recover information from the aggregate bit stream.
5.6 Octet timing
This function provides 8 kHz timing towards to the TE, the access digital section or the ET to enable voice
codecs to recover an octet structure and for other timing purposes as required.
5.7 Frame alignment
This function provides information to enable the TE, the access digital section or the ET to recover the
time-division multiplexed channels.
5.8 CRC-4 procedure
This function provides protection against false framing and for error performance monitoring of the access
digital section. The CRC-4 procedure shall be implemented according to ETR 001 [2], Option 2. This
includes the multiframe procedure defined in CCITT Recommendation G.704 [9].
5.9 M-channel
This function provides a bi-directional 4 kbit/s data channel for the implementation of management features
between ET and TE which is transparently transported in Sa4-bit of timeslot 0.
5.10 Power feeding
This optional function provides for remote feeding of the NT1 via the user-network interface as specified in
ETS 300 011 [1].
5.11 Operation and maintenance of the access digital section
This function supports actions and information required for control of the operation and maintenance of the
access digital section controlled by the ET as defined in ETR 001 [2], and utilises Sa5- and Sa6-bit as
defined in subclause 9.3.
The following categories of functions have been identified:
- commands regarding LT or NT1;
- information from LT or NT1;
- indications of defect conditions.
NOTE: The control of possible regenerators and additional maintenance functions concerning
the transmission system is outside the responsibility of the ET and is therefore not part
of the scope of this ETS, although it may be performed by the LT.
6 Signal transfer delay
The mean one way delay on the B-channels between the T and the V3 reference points shall not exceed
1 250 μs. In accordance with CCITT Recommendation G.114, this value is the mean of the propagation
times in
...