Business TeleCommunications (BTC); 64 kbit/s digital unrestricted leased line with octet integrity (D64U); Network interface presentation

Specification of the public network side of the interface and test procedures for compliance

Poslovne telekomunikacije (BTC) - Digitalni zakupljeni vodi za prenosno hitrost 64 kbit/s brez omejitev za prenašane signale in z ohranjanjem oktetov (D64U) - Omrežni vmesnik

General Information

Status
Published
Publication Date
31-Oct-1999
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Nov-1999
Due Date
01-Nov-1999
Completion Date
01-Nov-1999
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SLOVENSKI STANDARD
SIST ETS 300 288:1999
01-november-1999

Poslovne telekomunikacije (BTC) - Digitalni zakupljeni vodi za prenosno hitrost 64

kbit/s brez omejitev za prenašane signale in z ohranjanjem oktetov (D64U) -
Omrežni vmesnik

Business TeleCommunications (BTC); 64 kbit/s digital unrestricted leased line with octet

integrity (D64U); Network interface presentation
Ta slovenski standard je istoveten z: ETSI ETS 300 288 ed.1 (1994-01)
ICS:
33.040.50 Vodi, zveze in tokokrogi Lines, connections and
circuits
SIST ETS 300 288:1999 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 288:1999
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SIST ETS 300 288:1999
EUROPEAN ETS 300 288
TELECOMMUNICATION January 1994
STANDARD
Source: ETSI TC-BTC Reference: DE/BTC-02024
ICS: 33.020
ONP, leased line
Key words:
Business TeleCommunications (BTC);
64 kbit/s digital unrestricted leased line
with octet integrity (D64U)
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 1994. All rights reserved.
New presentation - see History box
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ETS 300 288: January 1994

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 Standards Approval Dept." at the address shown on the title page.

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ETS 300 288: January 1994
Contents

Foreword...........................................................................................................................................5

Introduction ........................................................................................................................................5

1 Scope ......................................................................................................................................7

2 Normative references ................................................................................................................7

3 Definitions................................................................................................................................. 8

4 Symbols and abbreviations.........................................................................................................8

5 Requirements............................................................................................................................9

5.1 Physical characteristics ...............................................................................................9

5.1.1 Connector specification.............................................................................9

5.1.2 Hardwired connection ............................................................................. 10

5.2 Electrical characteristics ............................................................................................ 10

5.2.1 Output port............................................................................................ 10

5.2.1.1 Signal coding.................................................................. 10

5.2.1.2 Waveform shape ............................................................ 10

5.2.1.3 Output timing.................................................................. 12

5.2.1.4 Output timing under failure conditions ............................... 12

5.2.1.5 Output return loss........................................................... 12

5.2.1.6 Impedance towards ground............................................. 12

5.2.1.7 Longitudinal conversion loss............................................. 12

5.2.1.8 Output signal balance...................................................... 12

5.2.2 Input port............................................................................................... 13

5.2.2.1 Signal coding.................................................................. 13

5.2.2.2 Input timing and jitter tolerance ........................................ 13

5.2.2.3 Input return loss.............................................................. 13

5.2.2.4 Input loss tolerance......................................................... 13

5.2.2.5 Immunity against reflections............................................. 13

5.2.2.6 Impedance towards ground............................................. 14

5.2.2.7 Longitudinal conversion loss............................................. 14

5.3 Safety...................................................................................................................... 14

5.3.1 General requirements ............................................................................. 14

5.3.2 Touch current......................................................................................... 14

5.4 Overvoltage protection .............................................................................................. 15

5.4.1 Surge simulation, common mode ............................................................. 15

5.4.2 Surge simulation, transverse mode between transmit and receive pairs...... 15

5.4.3 Mains simulation, common mode ............................................................. 15

5.4.4 Mains simulation, transverse mode .......................................................... 15

5.4.5 Impulse transfer from mains, common mode ............................................ 16

5.4.6 Impulse transfer from mains, transverse mode ......................................... 16

5.4.7 Conversion of common mode to transverse mode..................................... 16

5.5 Electromagnetic compatibility..................................................................................... 16

Annex A (normative): Test methods ............................................................................................. 17

A.1 General .................................................................................................................................. 17

A.1.1 Additional information to support the test..................................................................... 17

A.1.2 Equipment connection................................................................................................ 17

A.2 Test methods.......................................................................................................................... 17

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ETS 300 288: January 1994

A.2.1 Signal coding at output port........................................................................................ 17

A.2.2 Waveform shape at output port ..................................................................................18

A.2.3 Output timing under failure conditions..........................................................................19

A.2.4 Input coding, loss tolerance and immunity against reflections ........................................19

A.2.5 Return loss at input port.............................................................................................20

A.2.6 Longitudinal conversion loss .......................................................................................21

A.2.7 Impedance towards ground........................................................................................ 22

Annex B (normative): Code conversion rules ................................................................................. 23

Annex C (informative): Bibliography................................................................................................24

History .............................................................................................................................................25

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ETS 300 288: January 1994
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

harmonised standards for the support of the Directive on Open Network Provision (ONP) of leased lines

(92/44/EEC).
There are two other standards directly related to this ETS:

ETS 300 289: "Business TeleCommunications (BTC); 64 kbit/s digital unrestricted leased line with

octet integrity (D64U), Connection characteristics";

ETS 300 290: "Business TeleCommunications (BTC); 64 kbit/s digital unrestricted leased line with

octet integrity (D64U), Terminal equipment interface";

This ETS is based on information from CCITT Recommendations and ETSI publications and the relevant

documents are quoted where appropriate.
Introduction

The Council Directive on the application of Open Network Provision (ONP) to leased lines (92/44/EEC)

concerns the harmonisation of conditions for open and efficient access to, and use of, the leased lines

provided over public telecommunications networks and the availability throughout the Community (EEC) of

a minimum set of leased lines with harmonised technical characteristics.

Other countries outside the EEC may also choose to provide leased lines according to the standards

produced to support the Directive (of which this ETS is one of the set).

The consequence of the Directive is that Telecommunications Organisations within the EEC 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 interface presentation

requirements.
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ETS 300 288: January 1994
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ETS 300 288: January 1994
1 Scope

This ETS specifies the technical requirements and test principles for the network interface presentations of

Open Network Provision (ONP) 64 kbit/s digital unrestricted leased lines with octet integrity. These

presentations are codirectional.

A connection is presented via interfaces at Network Termination Points (NTP). This ETS defines the

network interface presented by the leased line provider and should be used in conjunction with the

companion standard, ETS 300 289 [6], which specifies the connection characteristics between the NTPs of

the leased line. Together, these documents describe the service offered.

This ETS is applicable to leased lines, including part time leased lines, whose establishment or release

does 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 in 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.152 (1988): "Error performance measuring
equipment for 64 kbit/s paths".
[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 Ib - safety".
[5] ETS 300 046-5 (1992): "Integrated Services Digital Network (ISDN); Primary
rate access - safety and protection, Part 5: Interface Ib - protection".
[6] ETS 300 289 (1994): "Business TeleCommunications (BTC); 64 kbit/s digital

unrestricted leased line with octet integrity (D64U), Connection characteristics".

[7] ISO/IEC 10173 (1991): "Information technology - Integrated Services Digital
Network (ISDN) primary access connector at reference points S and T".

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 300 288: January 1994
3 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 network termination points 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.

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 (TE): equipment intended to be connected to the public telecommunications network,

i.e.:

a) to be connected directly to the termination of a public telecommunication network; or

b) 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.
4 Symbols and abbreviations
For the purposes of this ETS, the following abbreviations apply:
D64U 64 kbit/s digital unrestricted ONP leased line with octet integrity
dc direct current
EMC Electro-Magnetic Compatibility
NTP Network Termination Point
ONP Open Network Provision
ppm parts per million

PRBS(2 -1) Pseudo Random Bit Sequence (as defined in § 2.1 of CCITT Recommendation

O.152 [2])
rms root mean square

RX Receive (a signal input at either the leased line interface or the test equipment,

see figure 1)
SELV Safety Extra-Low Voltage
TE Terminal Equipment

TX Transmit (a signal output at either the leased line interface or the test equipment,

see figure 1)
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ETS 300 288: January 1994
5 Requirements

The 64 kbit/s unrestricted leased line provides a bidirectional, point-to-point digital leased line with a usable

bit rate of 64 kbit/s and octet integrity, where the output timing is provided from the network. The interface

timing arrangements are codirectional.

NOTE: 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.
5.1 Physical characteristics

The physical connection arrangements shall be by a socket; however at the request of the user, and with

agreement of the leased line provider, an alternative means of connection may be provided, which shall

consist of a hardwired connection using insulation displacement connectors.

The use on the terminal equipment side of the interface of shielded cables may be necessary to meet

radiation and immunity requirements defined in Electro-Magnetic Compatibility (EMC) standards.

Therefore, the NTP may provide a point, or points, to which the shield, or shields, of the cable on the

terminal equipment side of the interface can be connected.

NOTE: The purpose of these points (if present) is to provide a path from the shield to a

common reference. The common reference point does not necessarily have to be
earthed.
5.1.1 Connector specification

Requirement: Where a connector is specified as the means of termination of the leased line, the network

interface shall provide an 8-contact socket of the type specified in ISO/IEC 10173 [7] with contact

assignments as specified in table 1.
Table 1: Contact assignment
Contact Network interface
1 & 2 Transmit pair
3 Shield reference point (if present)
4 & 5 Receive pair
6 Shield reference point (if present)
7 Unused
8 Unused

NOTE: 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 �˝˝˝˝˝˝˝˝˝˝˝˝»
” TX ˙˜˜˜˜˜˜˜˜˜˜˜˜˜>˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶ RX ”
” NETWORK ˙˜˜˜˜˜˜˜˜˜˜˜˜˜>˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶ TERMINAL ”
” INTERFACE ” ” EQUIPMENT ”
” ˙˜˜˜˜˜˜˜˜˜˜˜˜˜<˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶ ”
” RX ˙˜˜˜˜˜˜˜˜˜˜˜˜˜<˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶ TX ”
¨˝˝˝˝˝˝˝˝˝˝˝˝… INPUT OUTPUT ¨˝˝˝˝˝˝˝˝˝˝˝˝…
Figure 1

Test: There shall be a visual inspection that the socket is of the correct type. The contact assignments are

tested indirectly through the tests given in Annex A.
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ETS 300 288: January 1994
5.1.2 Hardwired connection

Requirement: Where one or more leased lines are being terminated as hardwired connections, these

connections shall be via an insulation displacement terminal block provided by the leased line provider. The

leased line provider shall provide information on the configuration of the insulation displacement terminals

used for each leased line interface.
Test: There is no test.

NOTE: All subsequent tests are carried out via the appropriate connection method.

5.2 Electrical characteristics
5.2.1 Output port
5.2.1.1 Signal coding

Requirement: The signal transmitted at the output port shall comply with the encoding rules given in

Annex B.

NOTE: When there is no input signal or octet timing is not present at the leased line distant

input or when there is a failure in the leased line connection, the octet timing at the

leased line output will not be meaningful.
Test: The test shall be according to Annex A, subclause A.2.1.
5.2.1.2 Waveform shape

Requirement: The pulse at the output port shall comply with the requirements given in table 2 and

figures 2 and 3, based on CCITT Recommendation G.703 [1].
Table 2: Waveform shape at output port
Pulse shape All pulses of a valid signal shall conform
(nominally rectangular) with the masks (see figures 2 and 3)
irrespective of the polarity.
Test load impedance 120 Ω non-reactive
Nominal peak voltage V of a mark (pulse) 1 V
Peak voltage of a space (no pulse) 0 ± 0,1 V
Nominal pulse width 3,9 μs for a single pulse
7,8 μs for a double pulse
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 300 288: January 1994
Figure 2: Pulse mask for single pulse
Figure 3: Pulse mask for double pulse
Test: The test shall be according to Annex A, subclause A.2.2.
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ETS 300 288: January 1994
5.2.1.3 Output timing

Requirement: Under normal operating conditions, the timing of the output signal shall be network timing.

NOTE: Network timing is timing that is derived from the source or sources of timing that are

used for the whole network. Therefore, the timing provided by the leased line will be

similar to that provided by other digital services.
Test: By declaration.
5.2.1.4 Output timing under failure conditions

Requirement: When there is a failure within the network and if a signal is presented at the interface

output, the timing of the output signal shall be 64 kbit/s ± 100 ppm.
Test: The test shall be according to Annex A, subclause A.2.3.
5.2.1.5 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.
5.2.1.6 Impedance towards ground

Requirement: The impedance towards ground of the output port shall be greater than 1 000 Ω for

frequencies in the range of 10 Hz to 1 MHz when measured with a sinusoidal test voltage of 2 V rms.

Where a shield reference point is provided, ground shall be pins 3 and 6 on the connecting socket or the

equivalent reference point on a hardwired connection. Where a shield reference point is not provided, the

leased line provider shall declare the point to be used for testing.
NOTE: This requirement is included to allow transformerless implementations.
Test: The test shall be according to Annex A, subclause A.2.7.
5.2.1.7 Longitudinal conversion loss

Requirement: The longitudinal conversion loss of the output port shall be greater than or equal to the

figures given in table 3. Where a shield reference point is provided, ground shall be pins 3 and 6 on the

connecting socket or the equivalent reference point on a hardwired connection. Where a shield reference

point is not provided, the leased line provider shall declare the point to be used for testing.

NOTE: This requirement is included to allow transformerless implementations.
Table 3: Output port longitudinal conversion loss
Frequency Longitudinal conversion loss
3,4 kHz 40 dB
3,4 kHz to 34 kHz decreasing 20 dB/decade from 40 dB to 20 dB
34 kHz to 256 kHz 20 dB
Test: The test shall be conducted according to Annex A, subclause A.2.6.
5.2.1.8 Output signal balance
There are no requirements for output signal balance under this ETS.
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ETS 300 288: January 1994

NOTE: The effects of the output signal imbalance are covered under the EMC Directive

(89/336/EEC).
5.2.2 Input port
5.2.2.1 Signal coding

Requirement: The input port shall accept, without error, signals encoded in accordance with encoding

rules of Annex B.

NOTE: The output signal is not defined when there is no input signal or octet timing present at

the leased line distant input.
Test: The test shall be according to Annex A, subclause A.2.4.
5.2.2.2 Input timing and jitter tolerance

The requirement for input timing and jitter tolerance is given in the companion standard ETS 300 289 [6].

5.2.2.3 Input return loss

Requirement: The input return loss with respect to 120 Ω at the interface shall be greater than or equal to

the values given in table 4 taken from CCITT Recommendation G.703 [1].
Table 4: Input port minimum return loss
Frequency range Return loss
4 kHz to 13 kHz 12 dB
13 kHz to 256 kHz 18 dB
256 kHz to 384 kHz 14 dB
Test: The test shall be according to Annex A, subclause A.2.5.
5.2.2.4 Input loss tolerance

Requirement: The input port shall correctly operate, without errors, with a 64 kbit/s input signal as defined

in subclauses 5.2.1.1 and 5.2.1.2 above but modified by an intervening pair with the following

characteristics:

a) attenuation that follows a ´f law with values throughout the range from 0 dB to 3 dB at 128 kHz; and

b) characteristic impedance of 120 Ω with a tolerance of ± 20 % in the frequency range from 200 kHz

to 1 MHz, and ± 10 % at 1 MHz.
Test: The test shall be according to Annex A, subclause A.2.4.
5.2.2.5 Immunity against reflections

Requirement: When a signal comprising a combination of a normal signal and an interfering signal is

applied to the input port, via an artificial cable with a loss in the range from 0 dB to 3 dB at 128 kHz, no

errors shall result due to the interfering signal.

The normal signal shall be a signal encoded according to Annex B, shaped according to the masks of

figures 2 and 3, with a binary content in accordance with a Pseudo Random Bit Sequence as defined in

§ 2.1 of CCITT Recommendation O.152 [2] (PRBS(211-1)).
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The interfering signal shall be the same as the normal signal except that the level shall be attenuated by

20 dB, the bit rate shall be within 64 kbit/s ± 100 ppm, and the timing shall not be synchronised to the

normal signal.
Test: The test shall be according to Annex A, subclause A.2.4.
5.2.2.6 Impedance towards ground

Requirement: The impedance towards ground of the input port shall be greater than 1 000 Ω for

frequencies in the range from 10 Hz to 1 MHz when measured with a sinusoidal test voltage of 2 V rms.

Where a shield reference point is provided, ground shall be pins 3 and 6 on the connecting socket or the

equivalent reference point on a hardwired connection. Where a shield reference point is not provided, the

leased line provider shall declare the point to be used for testing.
NOTE: This requirement is included to allow transformerless implementations.
Test: The test shall be according to Annex A, subclause A.2.7.
5.2.2.7 Longitudinal conversion loss

Requirement: The longitudinal conversion loss of the input port shall be greater than or equal to the

figures given in table 5. Where a shield reference point is provided, ground shall be pins 3 and 6 on the

connecting socket or the equivalent reference point on a hardwired connection. Where a shield reference

point is not provided, the leased line provider shall declare the point to be used for testing.

NOTE: This requirement is included to allow transformerless implementations.
Table 5: Input port longitudinal conversion loss
Frequency Longitudinal conversion loss
3,4 kHz 40 dB
3,4 kHz to 34 kHz decreasing 20 dB/decade from 40 dB to 20 dB
34 kHz to 256 kHz 20 dB
Test: The test shall be conducted according to Annex A, subclause A.2.6.
5.3 Safety

The tests associated with the requirements in this subclause are not suitable for use on installed leased

lines. Such tests may be applied to equipment of the kind used to provide the interface.

5.3.1 General requirements

Requirement: The leased line interface shall comply with the requirements for accessible parts of a SELV

circuit.

NOTE: Designers should take into account the minimum impedance towards ground specified

in this ETS.
Test: The test shall be conducted according to EN 60950 [3].
5.3.2 Touch current

This requirement recognises the fact that the equipment providing the NTP is likely to have a mains

electricity supply interface. If the equipment providing the NTP does not have a mains supply, this

requirement is not applicable.
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ETS 300 288: January 1994

For the purpose of the following requirement the connection point for the interface cable shield as defined

in ETS 300 046-4 [4] shall be pins 3 and 6 on the connecting socket or the equivalent reference point with

a hardwired connection.

Requirement: The touch current measured across the leased line interface shall not exceed 0,25 mA.

Test: The test shall be according to subclause 5.3 of ETS 300 046-4 [4].
5.4 Overvoltage protection

Overvoltage protection shall be tested in accordance with the methods described in ETS 300 046-5 [5] as

detailed below. The tests associated with these requirements are not suitable for use on installed leased

lines. The compliance criteria for the overvoltage protection tests of subclauses 5.4.1 to 5.4.7, based on

definitions used in CCITT Recommendations in the K-series, shall be:

The leased line interface shall operate properly within the limits of this specification and the

companion specification, ETS 300 289 [6], after the test without:
- the need for resetting the fault protection facilities; or
- the need to change any hardware component; or

- reloading of data other than data of a type declared in the operating instructions to be

unprotected data.

For the purpose of the following subclauses on protection, the term referred to as Ib in ETS 300 046-5 [5]

shall be deemed to be the point of test referred to in Annex A, subclau
...

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