SIST TBR 013 E1:2004

• Abstract:

  Specification of the attachment requirements for a terminal equipment interface and test procedures for compliance.

• Status: Published
• Publication Date: 30-Sep-2004
• ICS: 33.040.50 - Lines, connections and circuits
• Technical Committee: BTC - Business telecommunications
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Oct-2004
• Due Date: 01-Oct-2004
• Completion Date: 01-Oct-2004
• Mandate: T-147-2A
• Ref Project: ETSI TBR 013 ed.1 (1996-01) - Business TeleCommunications (BTC); 2 048 kbit/s digital structured leased lines (D2048S); Attachment requirements for terminal equipment interface

SIST TBR 013 E1:2004 specifies the attachment requirements and compliance test procedures for a terminal equipment interface used on Open Network Provision (ONP) 2 048 kbit/s digital structured leased lines (D2048S). It is published by SIST and corresponds to ETSI TBR 013 Edition 1. For designers, test labs, and buyers, it explains what the terminal interface must do at the network boundary so it can attach to the leased line network.

What does SIST TBR 013 E1:2004 specify?

SIST TBR 013 E1:2004 specifies the essential physical and electrical characteristics for connection of terminal equipment to the Network Termination Point (NTP) of ONP 2 048 kbit/s digital structured leased lines. It also gives the test principles used to check compliance.

The scope is limited to attachment requirements for a terminal equipment interface on 120 Ω interfaces with an information rate of 1 984 kbit/s and without restriction on binary content. The document says that compliance with these attachment requirements does not by itself guarantee end-to-end interoperability.

The standard is organized into:

• Scope, normative references, definitions and abbreviations
• Requirements in clause 4
• Annexes for tests, code definition, frame structure, compliance table and bibliography

Annex	What it covers
Annex A	Normative test methods and test conditions
Annex B	Normative definition of HDB3 code
Annex C	Normative definition of frame structure and CRC-4
Annex D	Normative TBR Requirements Table (TBR-RT)
Annex E	Informative bibliography

Customer premises wiring and installation between the terminal equipment and the NTP are outside the scope of the document. The standard also says that a terminal equipment interface conforming to this TBR will also conform with TBR 012 for connection to an ONP 2 048 kbit/s unstructured leased line.

What are the key requirements of SIST TBR 013 E1:2004?

SIST TBR 013 E1:2004 focuses on the interface conditions that prevent harm to the network and allow the leased line to recognise the signal correctly. The main requirements are in clause 4 and are checked by the tests in Annex A.

Physical connection

The terminal equipment shall provide a way to connect using solid wire conductors in the 0.4 mm to 0.6 mm range, either through connection contacts or through a wiring arrangement ending in unterminated solid conductors. In practice, this means the equipment must have a defined way to be attached to the line, even if no standardised connector is used.

Alternative means of connection may also be provided. This gives manufacturers flexibility, but the equipment still has to support the connection method used for compliance testing.

Output coding, waveform and timing

The output port shall use High Density Bipolar code of order 3 (HDB3). This keeps the transmitted stream compatible with the line code expected by the network.

The output pulse shape shall match the mask in clause 4.2.1.2 on a 120 Ω non-reactive load. The nominal mark amplitude is 3 V, spaces shall stay within 0 ± 0.3 V, and positive and negative pulses must stay symmetrical within the stated ratios. In practice, labs check both the waveform and the polarity balance so the signal does not distort the line.

Without any external timing reference, the output bit rate shall stay within 2 048 kbit/s ± 50 ppm. That matters because incorrect clock rate can prevent frame alignment and can create slips in the network.

Peak-to-peak output jitter shall stay within the limit in table 2, measured with the defined 40 Hz to 100 kHz filter band. When timing is derived from the leased line, the test injects defined sinusoidal jitter at the input. This is the part of the standard that controls timing instability so the line remains readable by the network.

Framing, CRC-4 and alarm bits

The output bit stream shall use the frame structure defined in Annex C. That includes the 256-bit frame, the multiframe arrangement, and the CRC-4 handling.

CRC-4 bits transmitted at the output shall match the data being sent. The A-bit shall be set to binary ZERO when the input to the terminal equipment contains continuous error-free frames and multiframes with the correct CRC-4 relationship. In practice, this means the terminal equipment must not falsely signal alarm when the received data is correct.

There is no requirement on the use of the E-bits, and there is no requirement on the use of the S bits. Those bits are either error indication bits or operator-reserved bits, so the standard leaves them outside the attachment requirements.

Input port, safety, overvoltage and EMC

There are no requirements on the input port beyond the overvoltage protection clauses. Safety requirements are not part of this TBR, and EMC requirements are also not part of this TBR.

For mains-powered equipment, the interface shall limit transferred surge energy to the stated common mode and transverse mode values, and common-mode surges shall not convert into a transverse mode voltage above the stated peak limit. These requirements protect the network interface rather than the terminal equipment itself.

Annex A also fixes the test environment. Tests are carried out with the specified connection method, at +19 °C to +25 °C and 10% to 75% relative humidity, unless the supplier states a different operating environment.

What terms does SIST TBR 013 E1:2004 define?

SIST TBR 013 E1:2004 defines the terms used to describe the frame, line code and network boundary.

• errored Sub-MultiFrame - An SMF where the calculated CRC-4 does not match the CRC-4 carried in the next SMF.
• frame - A sequence of 256 bits, with the first 8 bits defining the frame structure.
• leased lines - Telecommunications facilities with defined transmission characteristics between NTPs and no user-controlled switching.
• Network Termination Point (NTP) - The physical connections and access specifications that form part of the public network and are needed to reach it efficiently.
• Sub-Multiframe (SMF) - A sequence of 8 frames, or 2 048 bits, over which CRC-4 is calculated.
• terminal equipment - Equipment intended to connect to the public telecommunications network to send, process or receive information.
• HDB3 - High Density Bipolar code of order 3, the modified AMI line code used on the output port.
• PRBS - Pseudo Random Bit Sequence, used as a test pattern in the compliance methods.

Who uses SIST TBR 013 E1:2004?

SIST TBR 013 E1:2004 is used by manufacturers of terminal equipment, test laboratories, and conformity assessment teams working with ONP leased lines. They use it to design the interface, choose the connection method, and verify coding, timing, jitter and framing.

It is also useful to network operators, procurement teams, and quality managers who need to check whether equipment is suitable for attachment to a 2 048 kbit/s structured leased line. In practice, the document tells them what to test and what evidence to ask for when equipment is claimed to conform.

What changed in SIST TBR 013 E1:2004 from the previous edition?

SIST TBR 013 E1:2004 is stated to be identical to TBR 013 Edition 1.

Which standards are used with SIST TBR 013 E1:2004?

SIST TBR 013 E1:2004 cites these normative references and related standards:

Reference	What it contributes
CCITT Recommendation G.703	Physical and electrical characteristics of hierarchical digital interfaces
CCITT Recommendation G.704	Synchronous frame structures used at primary and secondary hierarchical levels
CCITT Recommendation O.151	Error performance measuring equipment for digital systems at the primary rate and above
CCITT Recommendation O.171	Timing jitter measuring equipment for digital systems
ETS 300 046-3	Safety and protection test method used for overvoltage-related checks
ETS 300 166	Basis for the 2 048 kbit/s hierarchical digital interface characteristics
ETS 300 418	Network interface presentation for D2048U and D2048S
ETS 300 419	Connection characteristics for D2048S
ETS 300 420	Terminal equipment interface for D2048S; this TBR is a subset of it
TBR 012	Attachment requirements for the 2 048 kbit/s unstructured leased line

What does the SIST TBR 013 E1:2004 document contain?

SIST TBR 013 E1:2004 contains the compliance structure, the line-code definition, the frame definition, and the test methods needed to check a terminal interface for D2048S attachment. Annex A gives the test setups and procedures for signal coding, waveform shape, clock accuracy, jitter, and frame structure.

Annex B defines the HDB3 code, and Annex C defines the 256-bit frame, bit allocation, and CRC-4 generation. Annex D provides the TBR Requirements Table, which is the compliance checklist, and Annex E lists background references.

SLOVENSKI STANDARD
01-oktober-2004
3RVORYQHWHOHNRPXQLNDFLMH%7&'LJLWDOQL]DNXSOMHQLYRGL]DSUHQRVQRKLWURVW
NELWVLQ]DQHVWUXNWXULUDQHVLJQDOH'83ULNOMXþLWYHQH]DKWHYH]D
YPHVQLNWHUPLQDOVNHRSUHPH
Business TeleCommunications (BTC); 2 048 kbit/s digital structured leased lines
(D2048S); Attachment requirements for terminal equipment interface
Ta slovenski standard je istoveten z: TBR 013 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.

TECHNICAL TBR 013
BASIS for January 1996
REGULATION
Source: ETSI TC-BTC Reference: DTBR/BTC-02037
ICS: 33.040.40
ONP, leased line, D2048S, terminal equipment
Key words:
Business TeleCommunications (BTC);
2 048 kbit/s digital structured leased lines (D2048S);
Attachment requirements for terminal equipment interface
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 1996. All rights reserved.

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TBR 013: January 1996
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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TBR 013: January 1996
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.10
4.1.2 Alternative means of connection .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 .11
4.2.1.4 Output jitter .12
4.2.1.5 Output structure.13
4.2.1.5.1 CRC-4.13
4.2.1.5.2 Use of the E-bits .13
4.2.1.5.3 Use of the A-bit .14
4.2.1.5.4 Use of the S bits .14
a
4.2.2 Input port .14
4.3 Safety.14
4.4 Overvoltage protection.14
4.4.1 Impulse transfer from mains, common mode .15
4.4.2 Impulse transfer from mains, transverse mode .15
4.4.3 Conversion of common mode to transverse mode .15
4.5 ElectroMagnetic Compatibility (EMC) .15
Annex A (normative): Test methods.16
A.1 General.16
A.1.1 Equipment connection .16
A.1.2 Test environment .16
A.2 Test methods .17
A.2.1 Signal coding at the output port .17
A.2.2 Waveform shape at output port .18
A.2.3 Clock accuracy at the output port .19
A.2.4 Output jitter .19
A.2.5 Frame structure .21
Annex B (normative): Definition of HDB3 code .22
B.1 General.22
B.2 Definition .22
Annex C (normative): Definition of frame structure .23

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TBR 013: January 1996
C.1 Frame structure . 23
C.2 CRC-4. 23
C.2.1 CRC-4 generation . 24
Annex D (normative): TBR Requirements Table (TBR-RT) . 25
Annex E (informative): Bibliography . 26
History. 27

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TBR 013: January 1996
Foreword
This Technical Basis for Regulation (TBR) has been produced by the Business Telecommunications
(BTC) Technical Committee of the European Telecommunications Standards Institute (ETSI).
This TBR results from a mandate from the Commission of the European Community (CEC) to provide
harmonized standards for the support of the Second Phase Directive (91/263/EEC).
This TBR is based on information from ITU-T 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 on 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 organisations within the EU shall make
available a set of leased lines between points in these countries with specified connection characteristics
and specified interfaces.
Two classes of standard will be used for the interfaces of terminal equipment designed for connection to
the ONP leased lines. European Telecommunications Standards (ETSs), which are voluntary, give the full
technical specifications for these interfaces, whereas Technical Basis for Regulations (TBRs) give the
essential requirements under the Second Phase Directive (91/263/EEC) for attachment to the leased
lines. This TBR is a subset of the corresponding ETS 300 420.
CCITT Recommendations G.703, G.704 and G.706, as qualified by ETS 300 166, are used as the basis
for the terminal interface.
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TBR 013: January 1996
Blank page
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TBR 013: January 1996
1 Scope
This TBR specifies the attachment requirements and corresponding test principles for a terminal
equipment interface for connection to the Network Termination Points (NTPs) of ONP 2 048 kbit/s digital
structured leased lines (D2048S) using 120 õ interfaces with an information rate of 1 984 kbit/s without
restriction on binary content. A terminal equipment interface that conforms to this TBR will also conform
with TBR 012 for connection to an ONP 2 048 kbit/s unstructured leased line.
The term "attachment requirements" in the context of this TBR describes the essential requirements for
access which have to be fulfilled under the Second Phase Directive (91/263/EEC). Conformance to these
requirements does not guarantee end-to-end interoperability.
This TBR is applicable to all interfaces designed for connection to the ONP 2 048 kbit/s structured leased
line. It covers the essential requirements for the physical and electrical characteristics of the terminal
equipment interface.
Customer premises wiring and installation between the terminal equipment and the NTP are outside the
scope of this TBR.
2 Normative references
This TBR 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 TBR 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 G.704 (1991): "Synchronous frame structures used at
primary and secondary hierarchical levels".
[3] CCITT Recommendation O.151 (1992), subclause 2.1: "Error performance
measuring equipment for digital systems at the primary rate and above".
[4] CCITT Recommendation O.171 (1992): "Timing jitter measuring equipment for
digital systems".
[5] ETS 300 046-3 (1992): "Integrated Services Digital Network (ISDN); Primary
rate access - safety and protection, Part 3: Interface I - protection".
a
NOTE: This TBR 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 E. In some cases the same publication may have been referenced in
both a normative and an informative manner.

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TBR 013: January 1996
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this TBR, the following definitions apply:
errored Sub-MultiFrame: A Sub-MultiFrame (SMF) where the calculated Cyclic Redundancy Check-4 bit
(CRC-4)1 does not correspond with the CRC-4 contained within the next SMF (see subclause C.2.2).
frame: A sequence of 256 bits of which the first 8 bits define the frame structure (see annex C).
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).
multiframe: A sequence of two SMFs containing the multiframe alignment word (see annex C).
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): Pseudo Random Bit Sequence (PRBS) (as defined in subclause 2.1 of CCITT
Recommendation O.151 [3]).
S bits: Bits 4 to 8 (bits S to S ) in frames not containing the frame alignment signal (see annex C).
a a4 a8
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).
Sub-Multiframe (SMF): A sequence of 8 frames, each of 256 bits, over which the CRC-4 is calculated
(see annex C).
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 TBR, the following abbreviations apply:
ac alternating current
AIS Alarm Indication Signal
AMI Alternate Mark Inversion
CRC-4 Cyclic Redundancy Check-4 bit
D2048S 2 048 kbit/s digital structured leased line
dc direct current
EMC ElectroMagnetic Compatibility
HDB3 High Density Bipolar code of order 3 (see annex B)
NTP Network Termination Point
ONP Open Network Provision
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TBR 013: January 1996
ppm parts per million
PRBS Pseudo Random Bit Sequence
RAI Remote Alarm Indication
RX RX is a signal input (at either the terminal equipment interface or the test
equipment, see figure 1)
SELV Safety Extra-Low Voltage
SMF Sub-MultiFrame
TX TX is a signal output (at either the terminal equipment interface or the test
equipment, see figure 1)
TBR-RT TBR Requirements Table
UI Unit Interval
4 Requirements
The terminal equipment interface is for use with 2 048 kbit/s structured leased lines which provide bi-
directional, point-to-point digital connections with an information transfer rate of 1 984 kbit/s without
restriction on binary content. Any structuring of the data within the transparent 1 984 kbit/s part of the
frame is the responsibility of the user.
4.1 Physical characteristics
Justification: Without a connection method defined, it is impossible for the terminal equipment to connect
to the network, therefore this is required for the terminal equipment to interwork with the network
(article 4f).
Currently no standardised connector is readily available. Consequently, the only method of connection that
can be specified in this TBR is the use of solid conductors of 0,4 mm to 0,6 mm. This TBR requires the
terminal equipment to be capable of presenting either a point for the attachment of unterminated solid
conductors, or solid conductors themselves (see subclause 4.1.1). It is a requirement that such a
connection method be available to be provided for use with the terminal equipment if necessary.
In order to allow connection to be made using other methods (e.g. connectors), the terminal equipment is
permitted to be supplied with a connection method suitable for use with those methods (see
subclause 4.1.2).
NOTE 1: The following are examples of arrangements that comply with the requirements. The
list below should not be regarded as an exhaustive list of all permitted arrangements:
a) a cord, permanently connected to the terminal equipment at one end and
unterminated at the other end, with wires that are solid conductors with
diameters in the range 0,4 mm to 0,6 mm;
b) a cord, connected via a plug and socket to the terminal equipment at one end
and unterminated at the other end, with wires that are solid conductors with
diameters in the range 0,4 mm to 0,6 mm;
c) an insulation displacement connector, designed to accept wires with solid
conductors with diameters in the range 0,4 mm to 0,6 mm, but with no cord;
d) a screw connector, designed to accept wires with solid conductors with
diameters in the range 0,4 mm to 0,6 mm, but with no cord;
e) the arrangement in b) plus one or more additional alternative cords with the
same plug or socket arrangement at the terminal end and any plug or socket at
the other end;
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TBR 013: January 1996
f) the arrangement in c) or d) plus one or more cords suitable for connection to the
terminal equipment at one end and any plug or socket at the other end.
The transmit pair is the output from the terminal equipment interface. The receive pair is the input to the
terminal equipment interface, as shown in figure 1. Where the terms "output" and "input" are used without
qualification in this TBR, they refer to the terminal equipment interface.
˝˝˝˝˝˝˝˝˝˝˝˝»OUTPUTINPUT˝˝˝˝˝˝˝˝˝˝˝˝»
”TX˙˜˜˜˜˜˜˜˜˜˜˜˜˜>˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶RX”
”NETWORK˙˜˜˜˜˜˜˜˜˜˜˜˜˜>˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶TERMINAL”
”INTERFACE””EQUIPMENT”
”˙˜˜˜˜˜˜˜˜˜˜˜˜˜<˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶”
”RX˙˜˜˜˜˜˜˜˜˜˜˜˜˜<˜˜˜˜˜˜˜˜˜˜˜˜˜˜¶TX”
¨˝˝˝˝˝˝˝˝˝˝˝˝…INPUTOUTPUT¨˝˝˝˝˝˝˝˝˝˝˝˝…
Figure 1
NOTE 2: The use of a shielded cord or cable may be necessary to meet radiation and immunity
requirements defined in ElectroMagnetic Compatibility (EMC) standards.
4.1.1 Hardwired connection
Requirement: The terminal equipment shall provide:
a) a set of connection contacts (e.g. an insulation displacement connector or a screw terminal block)
to which solid wire conductors with diameters in the range 0,4 mm to 0,6 mm may be connected; or
b) a wiring arrangement connected by any means to the terminal equipment, with unterminated solid
wire conductors with diameters in the range 0,4 mm to 0,6 mm at the end distant from the terminal
equipment.
Test: There is no test. All subsequent tests are carried out via the specified connection method.
4.1.2 Alternative means of connection
Any alternative means of connection may be provided in addition to the connection arrangements under
subclause 4.1.1.
4.2 Electrical characteristics
4.2.1 Output port
4.2.1.1 Signal coding
Justification: The correct signal coding is necessary for the output signals from the terminal equipment to
be received correctly at the input to the NTP, otherwise the leased line will not achieve frame alignment
and possibly send Alarm Indication Signal (AIS) forward within the network; therefore a requirement on
signal coding should be included for interworking with the network (article 4f).
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 conducted according to subclause A.2.1.
4.2.1.2 Waveform shape
Justification: The correct waveform shape serves to limit the voltages to line preventing harm to the
network (article 4d). It is also necessary for the output signals from the terminal equipment to be received
correctly at the input to the NTP, otherwise the leased line will not achieve frame alignment and possibly
send AIS forward within the network; therefore a requirement on the waveform shape should be included
for interworking with the network (article 4f).

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TBR 013: January 1996
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 [1].
Table 1: Waveform shape at output port
Pulse shape All marks of a valid signal must conform
(nominally rectangular) 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 õ 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
269 ns
(244 + 25)
20%
10%
V=100% 194 ns
10%
(244 - 50)
20%
Nominal pulse
50%
244 ns
219 ns
(244 - 25)
10% 10%
0%
10% 10%
20%
488 ns
(244 + 244)
Figure 2: Pulse mask for 2 048 kbit/s pulse
Test: The test shall be conducted according to subclause A.2.2.
4.2.1.3 Output timing
Justification: A certain level of timing accuracy is necessary for the bit stream to be received correctly at
the input to the NTP, otherwise the leased line will not achieve frame alignment and possibly send AIS
forward within the network; therefore a requirement on output timing should be included for interworking
with the network (article 4f). An output clock accuracy of 2 048 kbit/s ± 50 parts per million (ppm) is
sufficient for the input signal to be received correctly although this may result in a number of slips.
Requirement: In the absence of any external reference signal timing, the output signal shall have a bit
rate within the limits of 2 048 kbit/s ± 50 ppm.

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TBR 013: January 1996
Test: The test shall be conducted according to subclause A.2.3.
4.2.1.4 Output jitter
Justification: A high level of jitter causes error reports within some networks, therefore this requirement
is included to prevent harm to the network, (article 4d). It is necessary for the output signals from the
terminal equipment to be received correctly at the input to the NTP, otherwise the leased line will not
achieve frame alignment and possibly send AIS forward within the network; therefore a requirement on
output jitter should be included for interworking with the network (article 4f).
Requirement: The peak-to-peak output jitter shall not exceed the limits of table 2 when measured with a
bandpass filter with linear cut-off with the defined cut-off frequencies. At frequencies below the lower 3 dB
point, the attenuation of the high pass filter shall rise with a value equal to 20 dB per decade. At
frequencies above the upper 3 dB point, the attenuation of the low pass filtration shall rise with a value
greater than, or equal to, 60 dB per decade.
For the purpose of testing, any signal input from which the output timing is derived shall be provided with
the maximum tolerable input jitter, and with the maximum tolerable input frequency deviation, as specified
by the manufacturer.
Where the output timing of the terminal equipment is taken from the leased line, the input to the terminal
equipment shall be provided with components of sinusoidal jitter at points on the curve of table 3 and
figure 3.
NOTE: A separate requirement for output jitter at frequencies below 40 Hz is not required
because the measurement filter with a first order lower cut-off will allow the jitter to
have a spectrum whose amplitude rises at 20 dB/decade as the frequency reduces
below 40 Hz. Where timing is taken from the leased line, the test uses input jitter
frequencies from 20 Hz upwards.
Table 2: Maximum output jitter
Measurement filter bandwidth Output jitter
Lower cut-off Upper cut-off Unit Interval (UI) peak-to-peak
(high pass) (low pass) (maximum)
40 Hz 100 kHz 0,11 UI
Table 3: Input jitter for output jitter measurement
Peak-to-peak amplitude (UI) Frequency (Hz)
A1 A2 f1 f2 f3 f4
1,5 0,2 20 2 400 18 000 100 000

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TBR 013: January 1996
peak-to-peak jitterpeak-to-peak jitter
A1A1
A2A2
f1f1 f2f2 f3f3 f4f4
jitter frequencyjitter frequency
Figure 3: Input jitter for output jitter measurement
Test:
The test shall be conducted according to subclause A.2.4.
4.2.1.5 Output structure
Justification: It is necessary for the output signals from the terminal equipment to be received correctly at
the input to the NTP, otherwise the leased line will not achieve frame alignment and possibly send AIS
forward within the network; therefore a requirement on the output structure should be included for
interworking with the network (article 4f).
Requirement:
The bit stream transmitted at the output of the terminal equipment shall be structured as
defined in clause C.1.
Test:
The test shall be conducted according to subclause A.2.5.
4.2.1.5.1 CRC-4
Justification:
It is necessary for the CRC-4 from the terminal equipment to be correct at the output from
the terminal equipment, otherwi
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