ETSI EN 301 165 V1.1.3 (2002-08)

Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH); SDH leased lines; Network and terminal interface presentation

REN/TM-01098

Prenos in multipleksiranje (TM) - Sinhrona digitalna hierarhija (SDH) - Zakupljeni vodi SDH - Prikaz omrežnega in terminalskega vmesnika

General Information

• Status: Published
• Publication Date: 29-Aug-2002
• Technical Committee: TM 1 - TM Core networks, fibres and cables
• Current Stage: 12 - Completion
• Due Date: 11-Sep-2002
• Completion Date: 30-Aug-2002
• Mandate: T-324
• Ref Project: SIST EN 301 165 V1.1.3:2003 - Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH); SDH leased lines; Network and terminal interface presentation

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 301 165 V1.1.3:2003
01-april-2003
Prenos in multipleksiranje (TM) - Sinhrona digitalna hierarhija (SDH) - Zakupljeni
vodi SDH - Prikaz omrežnega in terminalskega vmesnika
Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH); SDH leased
lines; Network and terminal interface presentation
Ta slovenski standard je istoveten z: EN 301 165 Version 1.1.3
ICS:
33.040.20 Prenosni sistem Transmission systems
33.040.50 Vodi, zveze in tokokrogi Lines, connections and
circuits
SIST EN 301 165 V1.1.3:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 301 165 V1.1.3:2003

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SIST EN 301 165 V1.1.3:2003

ETSI EN 301 165 V1.1.3 (2002-08)
European Standard (Telecommunications series)


Transmission and Multiplexing (TM);
Synchronous Digital Hierarchy (SDH);
SDH leased lines;
Network and terminal interface presentation

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SIST EN 301 165 V1.1.3:2003
 2 ETSI EN 301 165 V1.1.3 (2002-08)



Reference
REN/TM-01098
Keywords
architecture, leased line, ONP, SDH,
transmission
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ETSI

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SIST EN 301 165 V1.1.3:2003
 3 ETSI EN 301 165 V1.1.3 (2002-08)
Contents
Intellectual Property Rights.4
Foreword.4
1 Scope.5
2 References.6
3 Definitions, symbols and abbreviations .7
3.1 Definitions.7
3.2 Symbols.9
3.3 Abbreviations.10
4 Network and terminal interfaces for Virtual Container (VC) leased line connection .11
4.1 Section layer functions for Network Termination (NT) and Terminal Equipment (TE).11
4.1.1 STM-1 section layers functions for NT and TE.11
4.1.2 STM-4 section layers functions for NT and TE.14
4.2 Path layer functions for NT .15
4.2.1 Network path layer functions for VC-4 leased line connections.15
4.2.2 Network path layer functions for lower order VC leased line connections .15
4.3 Path layers functions for TE.16
4.3.1 Terminal path layer functions for VC-4 leased line connections.16
4.3.2 Terminal path layer functions for lower order VC leased line connections.16
4.4 Mechanical characteristics for NT and TE interfaces.17
4.4.1 Connectors for the electrical STM-1 interface.17
4.4.2 Connectors for optical STM-N interfaces.17
4.5 Safety.18
4.6 AU/TU numbering scheme.18
5 Application of EN 300 417-2-1.18
6 Application of EN 300 417-3-1.20
7 Application of EN 300 417-4-1.22
8 Application of EN 300 417-6-1.28
Bibliography.30
History .31

ETSI

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SIST EN 301 165 V1.1.3:2003
 4 ETSI EN 301 165 V1.1.3 (2002-08)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in SR 000 314 (or the updates on the ETSI Web server)
which are, or may be, or may become, essential to the present document.
Foreword
This European Standard (Telecommunications series) has been produced by ETSI Technical Committee Transmission
and Multiplexing (TM).

National transposition dates
Date of latest announcement of this EN (doa): 30 November 2002
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 May 2003
Date of withdrawal of any conflicting National Standard (dow): 31 May 2003

ETSI

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SIST EN 301 165 V1.1.3:2003
 5 ETSI EN 301 165 V1.1.3 (2002-08)
1 Scope
The present document defines the atomic functions relevant for the interface presentations of Synchronous Digital
Hierarchy (SDH) leased lines at the Network Termination Point (NTP) and the Terminal Equipment (TE). It specifies
the technical requirements for electrical, optical, regenerator and multiplex section layer and SDH path layers. The
specification is presented as a delta information of the equipment specification of:
− EN 300 417-2-1 [8] for STM-1 electrical and optical and STM-4 optical section layer;
− EN 300 417-3-1 [9] for STM-1 and STM-4 regenerator section and multiplex section layer;
− EN 300 417-4-1 [10] for SDH path layers (VC-4, VC-3, VC-2 and VC-12);
− EN 300 417-6-1 [11] for synchronization layer functions.
The following physical section layers are used:
− STM-1 electrical interface;
− STM-1 optical intra-office interface;
− STM-1 optical short haul interfaces at 1 300 nm;
− STM-4 optical intra-office interface;
− STM-4 optical short haul interfaces at 1 300 nm.
The interface margins are defined such, that interconnection of different optical interfaces is possible when an
appropriate attenuation is inserted.
A connection is presented via interfaces at NTPs. The present document defines the network interface as presented by
the leased line provider and should be used in conjunction with the companion standard, EN 301 164 [5], specifying the
connection characteristics between NTPs of the leased line. The present document and the connection characteristic
standard together describe the technical characteristics of the leased line.
The present document is applicable for leased lines, including part time leased lines, for which the establishment or
release does not require any protocol exchange or other intervention at the NTP.
The present document is to ensure that the interface of the terminal equipment is compatible with the SDH leased line
interface. The present document is applicable to all interfaces designed for connection to the SDH leased lines.
Customer premises wiring and installation between terminal equipment and the NTP are outside the scope of the present
document.
The conformance test of the section and path layer functions will be addressed under work items EN 300 417-x-3
(x = 2, 3, 4 and 6). Some of the tests described in those ENs 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. The present
document does not include extra details concerning the implementation of tests, nor does it include information of any
relevant regulations. The present document does not specify the circumstances in which the tests given in
EN 300 417-x-3 (x = 2, 3, 4 and 6) are to be performed.
ETSI

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SIST EN 301 165 V1.1.3:2003
 6 ETSI EN 301 165 V1.1.3 (2002-08)
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
• A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same
number.
[1] EN 60950: "Safety of information technology equipment, including electrical business
equipment".
[2] IEC 60169-8 (1978): "Radio-frequency connectors - Part 8: R.F. coaxial connectors with inner
diameter of outer conductor 6.5 mm (0.256 in) with bayonet lock - Characteristic impedance 50 Ω
(Type BNC)".
[3] IEC 60169-13 (1976): "Radio-frequency connectors - Part 13: R.F. coaxial connectors with inner
diameter of outer conductor 5.6 mm (0.22 in) - Characteristic impedance 75 Ω (Type
1.6/5.6) - Characteristic impedance 50 Ω (Type 1.8/5.6) with similar mating dimensions".
[4] ISO/IEC 10173 (1998): "Information technology - Telecommunications and information exchange
between systems - Interface connector and contact assignments for ISDN primary rate access
connector located at reference points S and T".
[5] ETSI EN 301 164: "Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH);
SDH leased lines; Connection characteristics".
[6] ETSI ETS 300 147 (1997): "Transmission and Multiplexing (TM); Synchronous Digital Hierarchy
(SDH); Multiplexing structure".
[7] ETSI EN 300 417-1-1: "Transmission and Multiplexing (TM); Generic requirements of transport
functionality of equipment; Part 1-1: Generic processes and performance".
[8] ETSI EN 300 417-2-1: "Transmission and Multiplexing (TM); Generic requirements of transport
functionality of equipment; Part 2-1: Synchronous Digital Hierarchy (SDH) and Plesiochronous
Digital Hierarchy (PDH) physical section layer functions".
[9] ETSI EN 300 417-3-1: "Transmission and Multiplexing (TM); Generic requirements of transport
functionality of equipment; Part 3-1: Synchronous Transport Module-N (STM-N) regenerator and
multiplex section layer functions".
[10] ETSI EN 300 417-4-1: "Transmission and Multiplexing (TM); Generic requirements of transport
functionality of equipment; Part 4-1: Synchronous Digital Hierarchy (SDH) path layer functions".
[11] ETSI EN 300 417-6-1: "Transmission and Multiplexing (TM); Generic requirements of transport
functionality of equipment; Part 6-1: Synchronization layer functions".
[12] ITU-T Recommendation G.825 (1993): "The control of jitter and wander within digital networks
which are based on the synchronous digital hierarchy (SDH)".
[13] ITU-T Recommendation G.704 (1995): "Synchronous frame structures used at 1 544, 6 312,
2 048, 8 488 and 44 736 kbit/s hierarchical levels".
[14] IEC 60364-5-548 (1996): "Electrical installations of buildings - Part 5: Selection and erection of
electrical equipment - Section 548: Earthing arrangements and equipotential bonding for
information technology installations".
ETSI

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SIST EN 301 165 V1.1.3:2003
 7 ETSI EN 301 165 V1.1.3 (2002-08)
[15] ETSI EG 201 212: "Electrical safety; Classification of interfaces for equipment to be connected to
telecommunication networks".
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply.
process: generic term for an action or a collection of actions
function: "process" defined for digital transmission hierarchies (e.g. Plesiochronous Digital Hierarchy (PDH),
Synchronous Digital Hierarchy (SDH)), which acts on a collection of input information to produce a collection of
output information. A function is distinguished by the way in which characteristics of the collection, or of members of
the collection of output information differ from characteristics of members of the collection of input information
atomic function: "function" which if divided into simpler "functions" would cease to be uniquely defined for digital
transmission hierarchies. It is therefore indivisible from a network point of view. The following atomic functions are
defined in each network layer:
− bi-directional Trail Termination function (._TT), Trail Termination Source function (._TT_So), Trail
Termination Sink function (._TT_Sk) and Connection function (._C);
− between client and server layer networks three adaptation functions are defined: Adaptation Sink
function ._A_Sk, Adaptation Source function ._A_So, and the bi-directional Adaptation function ._A.
adaptation function: "atomic function" which passes a collection of information between layer networks by changing
the way in which the collection of information is represented
trail termination function: "atomic function" within a "layer" which generates, adds, and monitors information
concerning the integrity and supervision of "adapted information"
connection function: "atomic function" within a layer which, if connectivity exists, relays a collection of items of
information between groups of atomic functions. It does not modify the members of this collection of items of
information although it may terminate any switching protocol information and act upon it. Any connectivity restrictions
between inputs and outputs shall be stated
layer: concept used to allow the transport network functionality to be described hierarchically as successive levels; each
layer being solely concerned with the generation and transfer of its "characteristic information"
client/server layer: any two adjacent network layers are associated in a client/server relationship. Each transport
network layer provides transport to the layer above and uses transport from the layers below. The layer providing
transport is termed a "server", the layer using transport is termed "client"
Remote Defect Indication (RDI): signal which conveys the defect status of the characteristic information received by
the Trail Termination sink function back to the network element which contains the characteristic information
originating trail termination source function.
Examples of RDI signals are the Far End Receive Failure (FERF) bit(s) in SDH signals, the A-bit in
ITU-T Recommendation G.704 [13] structured 2 048 kbit/s signals and the alarm indication bit in other PDH multiplex
signals
Remote Error Indication (REI): signal which conveys either the exact or truncated number of error detection code
violations within the characteristic information (as detected by the trail termination sink function) back to the network
element which contains the characteristic information originating trail termination source function.
Examples of REI signals are the Far End Block Error (FEBE) bit(s) in SDH signals and the E-bit in
ITU-T Recommendation G.704 [13] structured 2 048 kbit/s signals
all-ONEs: entire capacity of the adapted or characteristic information is set to logic "1"
AU-4-AIS: STM-N signal in which the entire capacity of an Administrative Unit 4 (AU-4) is set to logic "1"
ETSI

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SIST EN 301 165 V1.1.3:2003
 8 ETSI EN 301 165 V1.1.3 (2002-08)
TU-m-AIS: STM-N signal in which the entire capacity of a TU-m is set to logic "1"
Characteristic Information (CI): signal of specific rate and format which is transferred within and between
"sub-networks", and presented to an "adaptation" function for "transport" by the server layer network
Remote Information (RI): information flow from sink direction to source direction of the same atomic function in
unidirectional representation, containing information to be transported to the remote end, such as RDI and REI
Access Point (AP): "reference point" where the output of an "adaptation" source function is bound to the input of a
"Trail Termination (TT) source", or where the output of a "trail termination sink" is bound to the input of an
"adaptation" sink function. The "access point" is characterized by the adapted client layer "characteristic information"
which passes across it. A bi-directional "access point" is formed by an associated contra-directional pair
Connection Point (CP): "reference point" where the output of a "trail termination source" or a "connection" is bound to
the input of another "connection", or where the output of a "connection" is bound to the input of a "trail termination
sink". The "connection point" is characterized by the information, which passes across it. A bi-directional "connection
point" is formed by the association of a contra-directional pair
NOTE 1: In the information model the connection point is called Connection Termination Point (CTP).
Termination Connection Point (TCP): special case of a "connection point" where a "trail termination" function is
bound to an "adaptation" function or a "connection" function
NOTE 2: In the information model the termination connection point is called Trail Termination Point (TTP).
defect: density of anomalies has reached a level where the ability to perform a required function has been interrupted.
Defects are used as input for performance management, the control of consequent actions, and the determination of fault
cause
ETSI

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SIST EN 301 165 V1.1.3:2003
 9 ETSI EN 301 165 V1.1.3 (2002-08)
3.2 Symbols
For the purposes of the present document, the following symbols apply:
The diagrammatic conventions and nomenclature used in the present document for adaptation, termination and
connection functions (used to describe the atomic functions) are taken from EN 300 417-1-1 [7] and are shown in
Figure 1.
Adaptation functions from Server layer Y to Client layer Z
Y/Z Sink Y/Z Y/Z
Source bidirectional
Compound Adaptation functions from Server layer Y to Client layer Z
Y/Z Y/Z Y/Z
Sink
Source bidirectional
Trail Termination functions in layer Y
YY Y
Sink Source bidirectional
Connection functions in layer Y
Y
Y
unidirectional bidirectional
Trail Termination function in layer Y and Adaptation function to layer Z
Y/Z Y/Z Y/Z
Y Y Y
Sink Source bidirectional

NOTE: If the above symbols are used for generic figures, i.e. not for specific layers, the layer references Y and Z
may be omitted. Alternatively, the references may be to the type of function or layer, e.g. supervision,
protection.
Figure 1: Symbols and diagrammatic conventions
ETSI

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SIST EN 301 165 V1.1.3:2003
 10 ETSI EN 301 165 V1.1.3 (2002-08)
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
A Adaptation function
AI Adapted Information
AIS Alarm Indication Signal
AP Access Point
AU Administrative Unit
AU-n Administrative Unit, level n
AUG Administrative Unit Group
C Connection function
CI Characteristic Information
CP Connection Point
CTP Connection Termination Point
ES Electrical Section
ES1 STM-1 Electrical Section
FEBE Far End Block Error
FERF Far End Receive Failure
I Informative
LC Layer Clock
LOF Loss Of Frame
LOM Loss Of Multiframe
LOP Loss Of Pointer
LOS Loss Of Signal
MS Multiplex Section
MS1 STM-1 Multiplex Section
MS4 STM-4 Multiplex Section
N Normative
N/R Not Relevant
NNI Network Node Interface
NT Network Termination
NTP Network Termination Point
OS Optical Section
OS1 STM-1 Optical Section
OS4 STM-4 Optical Section
PDH Plesiochronous Digital Hierarchy
PLM PayLoad Mismatch
RDI Remote Defect Indication
REI Remote Error Indication
RI Remote Information
RS Regenerator Section
RS1 STM-1 Regenerator Section
RS4 STM-4 Regenerator Section
RSOH Regenerator Section Overhead
S12 VC-12 path layer
S2 VC-2 path layer
S3 VC-3 path layer
S4 VC-4 path layer
S4/SX VC-4 path layer to lower order VC path layer
SDH Synchronous Digital Hierarchy
Sk Sink
So Source
SSF Server Signal Fail
STM Synchronous Transport Module
STM-N Synchronous Transport Module, level N
TCP Termination Connection Point
TE Terminal Equipment
TI Timing Information
TSF Trail Signal Fail
TT Trail Termination function
ETSI

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SIST EN 301 165 V1.1.3:2003
 11 ETSI EN 301 165 V1.1.3 (2002-08)
TTs Trail Termination supervisory function
TTP Trail Termination Point
TU Tributary Unit
TU-m Tributary Unit, level m
TUG Tributary Unit Group
TUG-m Tributary Unit Group, level m
UNEQ Unequipped
VC Virtual Container
VC-n Virtual Container, level n
4 Network and terminal interfaces for Virtual Container
(VC) leased line connection
4.1 Section layer functions for Network Termination (NT) and
Terminal Equipment (TE)
4.1.1 STM-1 section layers functions for NT and TE
The relevant section layer functions of electrical and optical STM-1 interfaces for NT and TE are shown in Figure 2 and
Figure 3 respectively. The details of the atomic functions shown in these figures are given in clauses 5 and 6 of the
present document. Two types of optical interfaces are relevant for leased line connections. These are the intra office
interface (I1) and the short haul interface at 1 300 nm (S1.1).
ETSI

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SIST EN 301 165 V1.1.3:2003
 12 ETSI EN 301 165 V1.1.3 (2002-08)
SD_CI
SD_CI
MS1-LC
MS1/SD MS1/S4 MS1/S4
STM1_TI MS1/SD
S1[5-8] S1[5-8]
RI_RDI
MS1 RI_REI MS1
MS1_CI
MS1_CI
MS1_C
RS1/MS1 RS1/MS1
RS1_AI
RS1_AI
RS1 RS1
RS1_CI RS1_CI
RS1_C
ES1/RS1
ES1/RS1
ES1_AI
ES1_AI
ES1 ES1
ES1_C
ES1_CI ES1_CI

Figure 2: Section layers of a STM-1 electrical interface for NT and TE
ETSI

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SIST EN 301 165 V1.1.3:2003
 13 ETSI EN 301 165 V1.1.3 (2002-08)
SD_CI
SD_CI
MS1-LC
MS1/SD MS1/S4 MS1/S4
STM1_TI MS1/SD
S1[5-8] S1[5-8]
RI_RDI
MS1 RI_REI MS1
MS1_CI
MS1_CI
MS1_C
RS1/MS1 RS1/MS1
RS1_AI
RS1_AI
RS1 RS1
RS1_CI
RS1_CI
RS1_C
OS1/RS1
OS1/RS1
OS1_AI
OS1_AI
OS1 OS1
OS1_C
OS1_CI OS1_CI

Figure 3: Section layers of an optical STM-1 interface for NT and TE
ETSI

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SIST EN 301 165 V1.1.3:2003
 14 ETSI EN 301 165 V1.1.3 (2002-08)
4.1.2 STM-4 section layers functions for NT and TE
The relevant section layer functions of optical STM-4 interfaces for NT and TE are shown in Figure 4. The details of
the atomic functions shown in these figures are given in clauses 5 and 6 of the present document. Two types of optical
interfaces are relevant for leased line connections. These are the intra office interface (I4) and the short haul interface at
1 300 nm (S4.1).
SD_CI
SD_CI S4_CI S4_CI SD_CI
MS4-LC
4 4
1 1
MS4/SD MS4/S4 MS4/S4
MS4/SD
STM4_TI
S1[5-8] S1[5-8]
RI_RDI
MS4 RI_REI MS4
MS4_CI
MS4_CI
MS4_C
RS4/MS4 RS4/MS4
RS4_AI
RS4_AI
RS4 RS4
RS4_CI
RS4_CI
RS4_C
OS4/RS4
OS4/RS4
OS4_AI
OS4_AI
OS4 OS4
OS4_C
OS4_CI OS4_CI

Figure 4: Section layers of an STM-4 interface for NT and TE
ETSI

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SIST EN 301 165 V1.1.3:2003
 15 ETSI EN 301 165 V1.1.3 (2002-08)
4.2 Path layer functions for NT
4.2.1 Network path layer functions for VC-4 leased line connections
There are no requirements on the VC-4 path layer functions for VC-4 leased line connections under the present
document.
NOTE: The connection characteristics of the VC-4 path layer are specified in the companion standard
EN 301 164 [5].
4.2.2 Network path layer functions for lower order VC leased line
connections
The relevant VC-4 path layer functions of an NT are shown in Figure 5. Their details are specified in clause 7 of the
present document.
The time taken for appearance of remote indication of defects and block errors depends on the processing time of the
equipment terminating the VC-4 and the round trip delay between that equipment and the leased line interface.
Therefore the timing criteria for setting and clearing of VC-4-RDI and VC-4-REI as given in the equipment
specification EN 300 417-4-1 [10] cannot be directly applied to the present document.
There are no requirements on the lower order VC path layer functions for lower order VC leased line connections under
the present document.
NOTE: The connection characteristics of the lower order VC path layers are specified in the companion standard
EN 301 164 [5].
SD_CI S12_CI S2_CI S3_CI
S12_CI S2_CI S3_CI
S4-LC
S4/SX S4/SX
S4_TI
S4_AI
S4_AI
RI_RDI
RI_REI
S4 S4
S4_C
S4_CI
S4_CI

Figure 5: NT path layer for lower order VC connections
ETSI

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SIST EN 301 165 V1.1.3:2003
 16 ETSI EN 301 165 V1.1.3 (2002-08)
4.3 Path layers functions for TE
4.3.1 Terminal path layer functions for VC-4 leased line connections
The relevant VC-4 path layer functions of a TE are shown in Figure 6. Their details are specified in clause 7 of the
present document. There are no requirements on the adaptation functions with two exceptions:
− they shall be timed by the S4-TI signal;
− VC-4 payload signals the mapping of which is not defined in ETS 300 147 [6] shall be scrambled when
6 7
emulation of the STM-N scrambler polynomial 1 + x + x in more than 8 consecutive bytes of the VC-4 payload
could occur. Scrambling is not necessary when the client layer take actions to exclude the emulation of the
scrambler polynomial in more than 8 consecutive bytes of the VC-4 payload.
NOTE: Scrambling provides security against malicious emulation of the SDH set-reset scrambler pattern.
Without scrambling a specific pattern could generate a long sequence of binary "0" which may be
detected as Loss Of Signal (LOS) or replicate the STM-N frame alignment word.
SD_CI
S4-LC
S4/client
S4/client
S4_TI
S4_AI
S4_AI
S4 RI_RDI, RI_REI S4
S4_C
S4_CI S4_CI

Figure 6: Terminal equipment path layer for VC-4 leased line connections
4.3.2 Terminal path layer functions
...