SIST ETS 300 418:1999

SLOVENSKI STANDARD
01-november-1999
Poslovne telekomunikacije (BTC) - Digitalni zakupljeni vodi za prenosno hitrost 2
048 kbit/s in za nestrukturirane in strukturirane signale (D2048U in D2048S) -
Omrežni vmesnik
Business TeleCommunications (BTC); 2 048 kbit/s digital unstructured and structured
leased lines (D2048U and D2048S); Network interface presentation
Ta slovenski standard je istoveten z: ETS 300 418 Edition 1
ICS:
33.040.50 Vodi, zveze in tokokrogi Lines, connections and
circuits
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 418
TELECOMMUNICATION November 1995
STANDARD
Source: ETSI TC-BTC Reference: DE/BTC-02021
ICS: 33.040.30
ONP, leased line, D2048U, D2048S, network interface
Key words:
Business TeleCommunications (BTC);
2 048 kbit/s digital unstructured and structured leased lines
(2048U and D2048S);
Network interface presentation
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 - secretariat@etsi.fr
X.400: Internet:
Tel.: +33 92 94 42 00 - Fax: +33 93 65 47 16
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 1995. All rights reserved.
New presentation - see History box

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ETS 300 418: November 1995
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 300 418: November 1995
Contents
Foreword .5
Introduction.5
1 Scope .7
2 Normative references.7
3 Definitions and abbreviations .8
3.1 Definitions .8
3.2 Abbreviations .8
4 Requirements.9
4.1 Physical characteristics.9
4.1.1 Hardwired connection.9
4.1.2 Socket specification.9
4.1.3 Shield connection point .10
4.2 Electrical characteristics .10
4.2.1 Output port .10
4.2.1.1 Signal coding .10
4.2.1.2 Waveform shape .10
4.2.1.3 Output timing under failure conditions .11
4.2.1.4 Impedance towards ground .12
4.2.1.5 Output return loss .12
4.2.1.6 Output signal balance.12
4.2.1.7 Output timing and jitter .12
4.2.2 Input port .12
4.2.2.1 Signal coding .12
4.2.2.2 Input return loss.12
4.2.2.3 Input loss tolerance.12
4.2.2.4 Immunity against reflections .13
4.2.2.5 Tolerable longitudinal voltages .13
4.2.2.6 Impedance towards ground .13
4.2.2.7 Input timing and jitter tolerance .13
4.3 Safety.13
4.3.1 General requirements.13
4.3.2 Touch current .14
4.4 Overvoltage protection.14
4.4.1 Surge simulation, common mode.14
4.4.2 Surge simulation, transverse mode between transmit and receive pairs.14
4.4.3 Mains simulation, common mode.14
4.4.4 Mains simulation, transverse mode.14
4.4.5 Impulse transfer from mains, common mode .15
4.4.6 Impulse transfer from mains, transverse mode .15
4.4.7 Conversion of common mode to transverse mode .15
4.4.8 Impulse transfer from auxiliary interface .15
4.5 ElectroMagnetic Compatibility (EMC) .15
Annex A (normative): Test methods.16
A.1 General.16
A.1.1 Additional information to support the test .16
A.1.2 Equipment connection .16

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ETS 300 418: November 1995
A.2 Test methods. 16
A.2.1 Signal coding at output port. 16
A.2.2 Waveform shape at output port. 17
A.2.3 Return loss at input port . 18
A.2.4 Input loss tolerance and immunity against reflections. 19
A.2.5 Tolerable longitudinal voltage and HDB3 input coding. 20
A.2.6 Impedance towards ground. 21
A.2.7 Output timing under failure conditions. 22
Annex B (normative): Definition of HDB3 code. 23
B.1 General. 23
B.2 Definition. 23
Annex C (informative): Bibliography . 24
History. 25

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ETS 300 418: November 1995
Foreword
This European Telecommunication Standard (ETS) has been produced by the Business
TeleCommunications (BTC) Technical Committee of the European Telecommunications Standards
Institute (ETSI).
This ETS resulted from a mandate from the Commission of the European Community (CEC) to provide
harmonized standards for the support of the Directive on Open Network Provision (ONP) of leased lines
(92/44/EEC).
In the case of the unstructured leased line, this ETS is intended to supersede ETS 300 246.
There are four other standards directly related to this ETS:
- ETS 300 247: "Open Network Provision (ONP) technical requirements; 2 048 kbit/s digital
unstructured leased line (D2048U); Connection characteristics";
- ETS 300 248: "Open Network Provision (ONP) technical requirements; 2 048 kbit/s digital
unstructured leased line (D2048U); Terminal equipment interface";
- ETS 300 419: "Business TeleCommunications (BTC); 2 048 kbit/s digital structured leased line
(D2048S); Connection characteristics";
- ETS 300 420: "Business TeleCommunications (BTC); 2 048 kbit/s digital structured leased line
(D2048S); Terminal equipment interface".
This ETS is based on information from ITU-T Recommendations and ETSI publications and the relevant
documents are quoted where appropriate.
Transposition dates
Date of adoption of this ETS 17 November 1995
Date of latest announcement of this ETS (doa): 28 February 1996
Date of latest publication of new National Standard 31 August 1996
or endorsement of this ETS (dop/e):
Date of withdrawal of any conflicting National Standard (dow): 31 August 1996
Introduction
The Council Directive on the application of ONP to leased lines (92/44/EEC) concerns the harmonization
of conditions for open and efficient access to, and use of, the leased lines provided over public
telecommunications networks, and the availability throughout the European Union (EU) of a minimum set
of leased lines with harmonized technical characteristics.
The consequence of the Directive is that telecommunications organizations within the EU shall make
available a set of leased lines between points in these countries with specified connection characteristics
and specified interfaces. Under the Second Phase Directive (91/263/EEC), terminal equipment for
connection to these leased lines will be required to fulfil certain essential requirements.
ETS 300 166 and CCITT Recommendation G.703 are used as the basis for the network interface
presentation requirements.
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ETS 300 418: November 1995
1 Scope
This ETS specifies the technical requirements and test principles for the network interface presentations
of ONP 2 048 kbit/s digital leased lines using 120 Ω interfaces. This includes:
- the 2 048 kbit/s digital unstructured leased line; and
- the 2 048 kbit/s digital structured leased line with an information transfer rate of 1 984 kbit/s without
restriction on binary content.
A connection is presented via interfaces at Network Termination Points (NTP). This ETS defines the
network interface as presented by the leased line provider and should be used in conjunction with the
appropriate companion standard, ETS 300 247 or ETS 300 419, specifying the connection characteristics
between the NTPs of the leased line. This ETS and the appropriate connection characteristics standard
together describe the technical characteristics of the leased line.
This ETS is applicable to leased lines, including part time leased lines, for which the establishment or
release do not require any protocol exchange or other intervention at the NTP.
This ETS covers the physical, mechanical and electrical characteristics of the network interface and
specifies the conformance tests for equipment of the kind that provides the interface presentation. Some
of the tests described in this ETS are not designed to be applied to the interface of an installed leased line;
such tests may be applied to equipment of the kind used to provide the interface. This ETS does not
include details concerning the implementation of the tests nor does it include information on any
regulations concerning testing. There is no requirement for each leased line to be tested in accordance
with this ETS before it is brought into, or returned into, service.
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 into it by amendment or revision. For undated references the
latest edition of the publication referred to applies.
[1] CCITT Recommendation G.703 (1991): "Physical/electrical characteristics of
hierarchical digital interfaces".
[2] CCITT Recommendation O.151 (1992): "Error performance measuring
equipment for digital systems at the primary rate and above".
[3] EN 60950 (1992): "Safety of information technology equipment including
electrical business equipment".
[4] ETS 300 046-4 (1992): "Integrated Services Digital Network (ISDN); Primary
rate access - safety and protection Part 4: Interface I - safety".
b
[5] ETS 300 046-5 (1992): "Integrated Services Digital Network (ISDN); Primary
rate access - safety and protection Part 5: Interface I - protection".
b
NOTE: This ETS also contains a number of informative references which have been included
to indicate the sources from which various material has been derived, hence they do
not have an associated normative reference number. Details of these publications are
given in annex C. In some cases the same publication may have been referenced in
both a normative and an informative manner.

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ETS 300 418: November 1995
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this ETS, the following definitions apply:
leased lines: The telecommunications facilities provided by a public telecommunications network that
provide defined transmission characteristics between NTPs and that do not include switching functions
that the user can control, (e.g. on-demand switching).
Network Termination Point (NTP): All physical connections and their technical access specifications
which form part of the public telecommunications network and are necessary for access to and efficient
communication through that public network.
PRBS(2 -1): A Pseudo Random Bit Sequence (PRBS) (as defined in subclause 2.1 of CCITT
Recommendation O.151 [2]).
Safety Extra-Low Voltage (SELV) circuit: A secondary circuit which is so designed and protected that
under normal and single fault conditions, the voltage between any two accessible parts and, for class 1
equipment, between any accessible part and the equipment protective earthing terminal does not exceed
a safe value (subclause 1.2.8.5 of EN 60950 [3]).
terminal equipment: Equipment intended to be connected to the public telecommunications network, i.e.:
- to be connected directly to the termination of a public telecommunication network; or
- to interwork with a public telecommunications network being connected directly or indirectly to the
termination of a public telecommunications network,
in order to send, process, or receive information.
3.2 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
AIS Alarm Indication Signal
AMI Alternate Mark Inversion
CRC-4 Cyclic Redundancy Check-4 bit
D2048S 2 048 kbit/s digital structured leased line
D2048U 2 048 kbit/s digital unstructured leased line
dc direct current
EMC ElectroMagnetic Compatibility
HDB3 High Density Bipolar code of order 3 (see annex B)
ISDN Integrated Services Digital Network
NTP Network Termination Point
ONP Open Network Provision
ppm parts per million
PRBS Pseudo Random Bit Sequence
rms root mean square
RX RX is a signal input (at either the leased line interface or the test equipment, see
figure 1)
SELV Safety Extra-Low Voltage
TX TX is a signal output (at either the leased line interface or the test equipment,
see figure 1)
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ETS 300 418: November 1995
4 Requirements
These requirements define the network interface presentation for:
- the 2 048 kbit/s digital unstructured leased line (D2048U) which provides a bidirectional
point-to-point digital connection with a usable bit rate of 2 048 kbit/s where timing is not provided
from the network. The provision of circuit timing is the responsibility of the user. No structuring of
the data is provided, or shall be required, by the network and any structuring is the responsibility of
the user; and
- the 2 048 kbit/s digital structured leased line (D2048S) which provides a bidirectional point-to-point
digital connection with an information transfer rate of 1 984 kbit/s without restriction on binary
content. The frame structure in the 2 048 kbit/s bit stream is defined in ETS 300 419. Any
structuring of the data within the transparent 1 984 kbit/s part of the frame is the responsibility of the
user.
NOTE 1: The network interface is not designed for power feeding.
NOTE 2: If equipment providing the interface requires a mains supply, the leased line provider
should bring this to the attention of the user so that the user can provide mains supply
back-up facilities, if required.
4.1 Physical characteristics
The connection arrangements provided by the leased line interface shall be suitable for hardwired
connection (see subclause 4.1.1); however, with the agreement of the user, an alternative means of
connection, using a socket, may be provided (see subclause 4.1.2).
The transmit pair is the output from the network interface. The receive pair is the input to the network
interface, as shown in figure 1. Where the terms "output" and "input" are used without qualification in this
ETS, they refer to the network interface.
Output Input
RX
TX
Network Terminal
Interface Equipment
RX TX
Input
Output
Figure 1
The use on the terminal equipment side of the interface of shielded cables may be necessary to meet
radiation and immunity requirements defined in ElectroMagnetic Compatibility (EMC) standards. Therefore
the NTP is required to provide a point for connection of the shield (see subclause 4.1.3).
4.1.1 Hardwired connection
Requirement: Where the leased line is being presented as a hardwired connection, the leased line
interface shall provide a means of terminating wire with solid conductors having diameters in the range 0,4
mm to 0,6 mm. The leased line provider shall provide information on the configuration of the means of
connection.
Test: There is no test. All subsequent tests are carried out via the specified connection method.
4.1.2 Socket specification
There is no constraint on the type of socket that may be used under this ETS.

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ETS 300 418: November 1995
NOTE: The intention is to specify the same socket as is specified for Integrated Services
Digital Network (ISDN) primary rate access; however this approach is not practicable
at present since connectors conforming to ISO/IEC 10173 are not available. A
requirement to use the ISDN primary rate socket may be added to this ETS when such
connectors are readily available.
4.1.3 Shield connection point
Requirement: The NTP shall provide a point, or points, to which the shield, or shields, of the cable on the
terminal side of the interface can be connected.
NOTE: The purpose of these points is to provide a path from the shield to a common
reference. The common reference point does not necessarily have to be earthed.
Test: There shall be a visual inspection that a point, or points, for connection of the shield, or shields, is
provided.
4.2 Electrical characteristics
4.2.1 Output port
4.2.1.1 Signal coding
Requirement: The signal transmitted at the output port shall comply with the High Density Bipolar code of
order 3 (HDB3) encoding rules (see annex B).
Test: The test shall be according to subclause A.2.1.
4.2.1.2 Waveform shape
Requirement: The pulse at the output port shall comply with the requirements given in table 1 and
figure 2, based on CCITT Recommendation G.703.
Table 1: Waveform shape at output port
Pulse shape (nominally rectangular) All marks of a valid signal shall conform
with the mask (see figure 2) irrespective
of the polarity. The value V corresponds
to the nominal peak voltage of a mark.
Test load impedance
120 Ω non-reactive
Nominal peak voltage V of a mark 3 V
Peak voltage of a space 0 ± 0,3 V
Nominal pulse width 244 ns
Ratio of the amplitudes of positive and negative 0,95 to 1,05
pulses at the centre of the pulse interval
Ratio of the widths of positive and negative 0,95 to 1,05
pulses at the nominal half amplitude

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ETS 300 418: November 1995
269 ns
(244 + 25)
20%
10%
V=100%
194 ns
10%
(244 - 50)
20%
Nominal pulse
50%
244 ns
219 ns
10% 10%
(244 - 25)
0%
10% 10%
20%
488 ns
(244 + 244)
Figure 2: Pulse mask for 2 048 kbit/s pulse
Test: The test shall be according to subclause A.2.2.
4.2.1.3 Output timing under failure conditions
Requirement: When there is a failure within the network and if a signal is presented at the interface
output (e.g. an Alarm Indication Signal (AIS)), the output timing shall be 2 048 kbit/s ± 50 parts per million
(ppm).
NOTE: AIS is encoded as a continuous stream of binary ONEs. It is used to indicate a loss of
capability in the direction from the network to the user. When an AIS signal is
transmitted by the network interface, its timing may:
- not be derived from network timing in the case where the leased line should be
providing network timing; or
- not be the timing provided by the user at the far end where the leased line
should be carrying user timing.
Test: The test shall be according to subclause A.2.7.

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ETS 300 418: November 1995
4.2.1.4 Impedance towards ground
Requirement: The impedance towards ground of the output port shall be greater than 1 000 Ω for
frequencies in the range 10 Hz to 1 MHz when measured with a sinusoidal test voltage of 2 V root mean
square (rms). Ground (in this context) shall be the shield connection point defined in subclause 4.1.3.
NOTE: This requirement is included to allow transformerless implementations.
Test: The test shall be according to subclause A.2.6.
4.2.1.5 Output return loss
There are no requirements for output return loss under this ETS.
NOTE: A requirement for output return loss may be added to this ETS when appropriate
specifications become available.
4.2.1.6 Output signal balance
There are no requirements for output signal balance under this ETS.
NOTE: The effects of the output signal imbalance are covered under the EMC Directive
(89/336/EEC).
4.2.1.7 Output timing and jitter
NOTE: Output timing requirements and jitter limits for the leased line are specified in the
appropriate connection standard, ETS 300 247 or ETS 300 419.
4.2.2 Input port
4.2.2.1 Signal coding
Requirement: The input port shall correctly de
...