ETSI TS 102 143 V1.1.1 (2003-05)

SLOVENSKI STANDARD
SIST-TS ETSI/TS 102 143 V1.1.1:2005
01-januar-2005
Storitve in protokoli za napredna omrežja (SPAN) – MTP/SCCP/SSCOP in SIGTRAN
(prenos SS7 preko IP) – Uporabniška prilagodilna plast (SUA) krmilnega dela
signalizacijske zveze [privzeti SIGTRAN–SUA–14 (december 2002), spremenjen]
Services and Protocols for Advanced Networks (SPAN); MTP/SCCP/SSCOP and
SIGTRAN (Transport of SS7 over IP); Signalling connection control part User Adaptation
layer (SUA) [Endorsement of SIGTRAN-SUA-14 (December 2002), modified]
Ta slovenski standard je istoveten z: TS 102 143 Version 1.1.1
ICS:
33.040.01 Telekomunikacijski sistemi Telecommunication systems
na splošno in general
SIST-TS ETSI/TS 102 143 V1.1.1:2005 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS ETSI/TS 102 143 V1.1.1:2005

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SIST-TS ETSI/TS 102 143 V1.1.1:2005

ETSI TS 102 143 V1.1.1 (2003-05)
Technical Specification


Services and Protocols for Advanced Networks (SPAN);
MTP/SCCP/SSCOP and SIGTRAN (Transport of SS7 over IP);
Signalling connection control part User Adaptation layer (SUA)
[Endorsement of SIGTRAN-SUA-14 (December 2002), modified]

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SIST-TS ETSI/TS 102 143 V1.1.1:2005
 2 ETSI TS 102 143 V1.1.1 (2003-05)



Reference
DTS/SPAN-130264
Keywords
MTP, SCCP, SIGTRAN, SS7, SUA,
endorsement
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ETSI

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SIST-TS ETSI/TS 102 143 V1.1.1:2005
 3 ETSI TS 102 143 V1.1.1 (2003-05)
Contents
Intellectual Property Rights.4
Foreword.4
Endorsement notice .4
Introduction .4
1 Scope.5
2 References.5
3 Abbreviations.6
4 General considerations applicable to transport of Signalling System No. 7 over IP.6
4.1 Transport protocol.7
4.2 SCTP considerations.7
4.3 National options.7
4.4 Application Server mode.7
4.5 Application Server state handling.7
4.6 Dynamic registration.7
4.7 Message distribution to the Application Server.7
4.8 Receipt of unrecognized messages.7
5 General considerations applicable to SUA.7
5.1 National options.7
5.2 Dynamic registration.8
5.3 Message distribution to the Application Server.8
5.4 SUA procedures.8
5.5 Class 3 operation .8
5.6 N-PCSTATE primitive.8
6 Modifications to SUA-14 .8
Annex A (informative): Bibliography.22
History .23

ETSI

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SIST-TS ETSI/TS 102 143 V1.1.1:2005
 4 ETSI TS 102 143 V1.1.1 (2003-05)
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).
All published ETSI deliverables shall include information which directs the reader to the above source of information.
Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Services and Protocols for
Advanced Networks (SPAN).
Endorsement notice
The elements of Internet Engineering Task Force Internet Draft draft-ietf-sigtran-sua-14 [3], apply with the following
modifications.
Introduction
The present document records the changes to the Internet Engineering Task Force (IETF) draft SUA document. IETF
drafts are transient documents, eventually the SUA draft is expected to be replaced with an RFC, which will persist on
the IETF website. However, ETSI will keep a copy of the IETF draft on its website until the present document is
replaced. See [3] below for more information.
ETSI

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 5 ETSI TS 102 143 V1.1.1 (2003-05)
1 Scope
The present document is applicable to the international network and does not intend to restrict national networks.
However to facilitate interworking, its adoption within national networks is preferred.
The present document specifies the Signalling Connection Control Part (SCCP) User Adaptation layer signalling
protocol for connecting SCCP Users via Signalling System No. 7 SCCP international relay points and signalling
gateways to SCCP Users in an Internet Protocol (IP) managed network.
The present document endorses and constrains where relevant the SIGTRAN SUA of [3].
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 and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
[1] ETSI EN 300 009-1: "Signalling Connection Control part (SCCP) (connectionless and connection-
oriented) to support international interconnection".
[2] ETSI EN 300 008-1: "Integrated Services Digital Network (ISDN); Signalling System No.7;
Message Transfer Part (MTP) to support international interconnection; Part 1: Protocol
specification [ITU-T Recommendations Q.701, Q.702, Q.703, Q.704, Q.705, Q.706, Q.707 and
Q.708 modified] ".
[3] IETF Internet Draft draft-ietf-sigtran-sua-14: "Signalling Connection Control Part User Adaptation
Layer (SUA)".
NOTE: At http://www.ietf.org/internet-drafts/draft-ietf-sigtran-sua-14.txt.
[4] ITU-T Recommendation Q.714: "Specifications of Signalling System No. 7, Signalling connection
control part procedures".
[5] ETSI EG 201 693: "Integrated Services Digital Network (ISDN); Signalling System No.7; Master
list of codepoints".
[6] ITU-T Recommendation Q.704: "Specifications of Signalling System No. 7, Message Transfer
Part, Signalling network functions and messages".
[7] ITU-T Recommendation Q.711: "Signalling System No.7 - Functional Description of the
Signalling Connection Control Part".
[8] ITU-T Recommendation Q.713: "Signalling connection control part formats and codes".
[9] ITU-T Recommendation Q.774: "Transaction capabilities procedures".
[10] ETSI TS 102 144: "Services and Protocols for Advanced Networks (SPAN); MTP/SCCP/SSCOP
and SIGTRAN; SCTP".
[11] ETSI TS 102 141: "Services and Protocols for Advanced Networks (SPAN); MTP/SCCP/SSCOP
and SIGTRAN (Transport of SS7 over IP); Message transfer part 2 User Adaptation layer (M2UA)
[Endorsement of RFC 3331 (2002), modified]".
ETSI

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[12] ETSI TS 102 142: "Services and Protocols for Advanced Networks (SPAN); MTP/SCCP/SSCOP
and SIGTRAN (Messag of SS7 over IP); Message transfer part 3 User Adaptation layer (M3UA)
[Endorsement of RFC 3332 (2002), modified]".
[13] IETF RFC 3332 (2002): "Signaling System 7 (SS7) Message Transfer Part 3 (MTP3) - User
Adaptation Layer (M3UA)", G. Sidebottom, K. Morneault, J. Pastor-Balbas.
[14] IETF RFC 2119: "Key words for use in RFCs to Indicate Requirement Levels".
3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ACTIVE ASP ACTIVE
AS Application Server
ASP AS Process
ASPSM Application Server Process State Maintenance
BEAT heartBEAT
BEAT ACK heartBEAT ACK
CLDR ConnectionLess Data Response
CLDT ConnectionLess Data Transfer
COAK COnnection AcKnowledge
CODA Connection Oriented Data Acknowledge
CODT Connection Oriented Data Transfer
COIT Connection Oriented Inactivity Test
CORE COnnection REquest
DAUD Destination state AUDit
DAVA Destination AVAilable
DRST Destination ReSTricted
DUNA Destination UNAvailable
DUPU Destination User Part Unavailable
ERR ERroR
IANA Internet Assigned Numbers Authority
IETF Internet Engineering Task Force
IP Internet Protocol
RESCO RESet COnfirm
RESRE RESet REquest
RFC Request For Comment (IETF standard)
RIL Restricted Importance Level
RKM Routing Key Management
SCCP Signalling Connection Control Part
SG Signalling Gateway
SGP SG Process
SS7 Signalling System Number 7
SSC SCCP/Subsystem Congested
SSN SubSystem Number
SUA SCCP User Adaptation layer
4 General considerations applicable to transport of
Signalling System No. 7 over IP
The elements of SIGTRAN adaptation layers apply with the following exceptions and restrictions. The considerations
in this clause are common to TS 102 141 [11], TS 102 142 [12] and the present document.
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4.1 Transport protocol
The protocol underlying the adaptation layer for transport of SS No.7 signalling information in IP networks shall be
SCTP.
4.2 SCTP considerations
The SCTP used shall conform to TS 102 144 [10].
The SCTP payload protocol identifier for messages pertaining to an adaptation layer shall be the one assigned by IANA
for that layer. Adaptation layer messages received with neither the IANA payload protocol identifier nor payload
protocol identifier equal to 0 shall be silently discarded.
Unordered user messages shall not be used.
4.3 National options
No national options excluded by ETSI standards shall apply to the present document.
4.4 Application Server mode
The Broadcast mode shall not be used.
4.5 Application Server state handling
If multiple Application Server Processes (ASPs) are used within the AS, the AS shall be considered active when the
first ASP becomes active, and shall remain active until the last ASP becomes inactive.
4.6 Dynamic registration
Dynamic registration shall not be used for configuration management. The configuration of the system shall be
modified only by the management system, and not by the protocol itself.
4.7 Message distribution to the Application Server
The key to enable messages to be distributed to the appropriate AS shall have a granularity no smaller than is allowed
by the network management messages appropriate to that layer.
4.8 Receipt of unrecognized messages
If a message with an unrecognized message class is received, a Management Error message shall be returned with Error
Code "Unsupported Message Class".
5 General considerations applicable to SUA
5.1 National options
No national options excluded by EN 300 009-1 [1] and EN 300 008-1 [2] shall apply to the present document.
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 8 ETSI TS 102 143 V1.1.1 (2003-05)
5.2 Dynamic registration
Dynamic registration of Routing Keys shall not be used for configuration management. The configuration of the system
shall be modified only by the management system, and not by the protocol itself.
5.3 Message distribution to the Application Server
The Routing Key to enable messages to be distributed to the appropriate AS shall have a granularity no smaller than
Point Code + SSN.
5.4 SUA procedures
The SUA procedures shall be as defined in [3] augmented by ITU-T Recommendation Q.714 [4] as modified by
EN 300 009-1 [1], except where otherwise defined below.
5.5 Class 3 operation
Class 3 operation is not in the scope of the present document.
5.6 N-PCSTATE primitive
The N-PCSTATE primitive's signalling point status parameter (see ITU-T Recommendation Q.711 [7] clause 6.3.2.2.5)
has in [3] been extended to convey information about the restricted status of the signalling point. However, this shall not
be used.
6 Modifications to SUA-14
Modificiations to [3] are listed according to the section or subsection of [3].
Section 1 Introduction
ANSI references do not apply. Add a reference "[ITU SCCP]".
NOTE: SCCP user messages are transported between two signalling endpoints.
Subsection 1.2 Terminology
Routing Key: Dynamic registration of Routing Keys shall not be used for configuration management. The
configuration of the system shall be modified only by the management system, and not by the protocol itself.
Add the definition of Network Appearance taken from RFC 3332 [13] (which has been extended for SUA) viz:
• "Network Appearance - The Network Appearance is an SUA local reference (typically an integer) shared by
SG and AS that together with a Signalling Point Code or global title uniquely identifies an SS7 node by
indicating the specific SS7 network it belongs to".
Subsection 1.3.1 Protocol Architecture for Connectionless Transport
NOTE: The entity labelled "SEP or STP" is just an SEP here since it contains an SCCP User.
Subsection 1.3.1.1
NOTE: The SG can act as an endpoint with messages routed to it also by global title, if the global title translation
there yields the point code of the SG itself.
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Subsection 1.3.1.2 SG as relay-point
NOTE: Global Title Translation yields an "entity set", not an "entity". A way of viewing the AS is then as an
"entity set", with each ASP that the AS uses viewed as an "entity" within the set.
Subsection 1.3.2 Protocol Architecture for Connection-Oriented Transport
Replace the first two sentences by:
"In this architecture, the SCCP and SUA layers in the SGP interface to support connection-oriented data transfer
between SEP and ASP. Connection sections are setup when routing the Connect Request messages from SEP via SGP
to ASP or the other way".
NOTE: The entity labelled "SEP or STP" is just an SEP here since it contains an SCCP User.
Subsection 1.4.2 SCCP Protocol Class Support
Protocol class 3 is not in the scope of the present document.
Subsection 1.4.4 Interworking with SCCP Network Management Functions
ANSI references do not apply.
• N-STATE is defined in ITU-T Recommendation Q.711 [7], clause 6.3.2.3.2, table 16/Q.711.
• N-PCSTATE is defined in ITU-T Recommendation Q.711 [7], clause 6.3.2.3.3, table 17/Q.711.
• N-COORD is defined in ITU-T Recommendation Q.711 [7], clause 6.3.2.3.1, table 15/Q.711.
Subsection 1.4.5 Support for the management between the SGP and ASP.
The SUA shall also provide interworking with SCCP management functions at the SG to inform concerned SCCP users
in the SS No.7 network about the availability, accessibility and congestion status of SUA/SUA users in the managed IP
network.
Subsection 1.5 Internal Functions Provided in the SUA Layer
Transaction ID shall not be used for Routing Key Information.
Dynamic registration shall not be used to provision Routing Key information.
Subsection 1.5.1 Address Mapping at the SG
Replace occurrences of "t (r)""by "T(r)".
If messages are discarded when there is no address match, a report shall be made to Layer Management.
Subsection 1.5.3 Address Mapping Function at a Relay Node
It is preferable to route messages to the SG on Global Title within the SS No.7 network, rather than on SSN (+ PC), if
the relay function is to be invoked at the SG (with the SG's incoming SCCP itself performing a Global Title
Translation). This helps the SG to avoid performing multi-point code working at its MTP level.
If the relay function is to be invoked for messages from the IP network directly to the SS No.7 network, resolution of
the address information shall yield the information required in ITU-T Recommendation Q.714 [4], clause 2.2.2.
Subsection 1.5.4 SCTP Stream Mapping
A set of signalling messages requiring to be delivered in the same sequence as they are sent shall use the same SCTP
stream.
Sequenced delivery shall be used for SUA management messages.
Protocol class 3 is not in the scope of the present document.
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Subsection 1.5.6 Congestion Management
How local and IP network congestion is reported to SUA is nodal implementation-dependent. But SUA shall be told if
such congestion occurs.
When an SG determines that the transport of SS7 messages is encountering congestion, the SG shall trigger SS7 SCCP
Congestion messages to originating SS7 nodes according to the congestion procedures of ITU-T
Recommendation Q.714 [4].
The triggering of SS No.7 SCCP Management messages from an SG shall be done if congestion occurs. The means of
doing this is a nodal implementation-dependent function.
The SUA layer at an ASP or IPSP shall indicate local congestion to an SUA peer.
When an SG receives a congestion message (SCON) from an ASP, and the SG determines that an endpoint.
is now encountering congestion, it shall trigger congestion procedures as per ITU-T Recommendation Q.714 [4].
The receiving node shall be able to detect local congestion and inform the transmitting node of this, by whatever means.
Subsection 1.6.1 Definition of the upper boundary
ANSI references do not apply.
Class 3 operation is not in the scope of the present document. If a connection request asks for class 3, and the node
supports class 2 but not class 3, the class shall be lowered to 2 in the reply.
• N-EXPEDITED DATA and N-RESET pertain to class 3 operation, and are not in the scope of the present
document.
• N-INFORM is defined in ITU-T Recommendation Q.711 [7], clause 6.1.1.3.2, table 8/Q.711.
• N-UNIT DATA is defined in ITU-T Recommendation Q.711 [7], clause 6.2.2.3.1, table 12/Q.711.
• N-NOTICE is defined in ITU-T Recommendation Q.711 [7], clause 6.2.2.3.2, table 13/Q.711.
• Add N-COORD, N-STATE and N-PCSTATE primitives, defined in ITU-T Recommendation Q.711 [7],
clause 6.3.2, tables 14/Q.711, 15/Q.711, 16/Q.711 and 17/Q.711.
Subsection 1.6.3 Definition of the Boundary between SUA and Layer Management
Dynamic registration of RK shall not be used.
Add the primitive M-ERROR_occ indication, in the direction SUA to LM, with purpose SUA reports an error condition
to LM.
Subsection 3.1 Common Message Header
Replace the last paragraph with:
• "Optional parameters shall occur at most once in an SUA message".
Add another paragraph:
• "The Reserved field shall be set to 0 in messages sent, and shall not be examined on reception".
Subsection 3.1.2 Message Classes
MGMT messages shall use SCTP stream 0, SNM messages shall use stream 0, ASPSM messages shall use stream 0
(apart from BEAT ACK which can use any stream), ASPTM messages shall use a traffic stream, CL and CO messages
shall use any but stream 0.
NOTE: Stream 0 shall be used for SNM messsages, since DUNA, DAVA, DUPU messages referring-to the same
destination must be delivered in the order in which they are sent, and DUNA and DAVA messages
without SSN parameters can contain a list of destinations in their Affected Point Code parameter. The list
in a DUNA or DAVA might contain some the same, and some different, destinations as a following
DAVA or DUNA respectively.
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The default Importance value for MGMT messages shall be 8 for NTFY and 7 for ERR.
The default Importance value for SNM messages shall be 6 for DUNA, DAVA, DUPU, DAUD and SCON, it shall be 5
for DRST.
The default Importance value for ASPSM messages shall be 8 for all except BEAT ACK, which shall be 2.
The default Importance value for ASPTM messages shall be 8.
The default Importance values for CL and CO messages shall be the same as those defined in ITU-T Recommendation
Q.714 [4] table 2/Q.714 for the equivalent messages. The maximum Importance values for CL and CO messages shall
be the same as those defined in ITU-T Recommendation Q.714 [4] table 2/Q.714 for the equivalent messages.
Routing Key Management messages shall not be sent.
If a Routing Key Management message is received an Error (ERR) message shall be returned with Error Code
"Unsupported Message Class", the RKM message shall be discarded and a report made to Layer Management.
Subsection 3.1.3 Message Types
Signalling network management messages:
Destination Restricted (DRST) shall only be used when equivalent to an SCCP N-COORD primitive, but this is
required only for separate nodes containing replicated subsystems, where these nodes also support SCCP management
procedures.
DRST equivalent to the SCCP N-PCSTATE indication primitive with Signalling point status parameter set to
"destination restricted" shall not be sent. If such a N-PCSTATE primitive is received in the SUA, it shall be discarded
and a report made to Layer Management.
Application Server Process State Maintenance messages (ASPSM):
Heartbeat is not required and BEAT shall not be sent. If a BEAT is received, a BEAT ACK shall be sent in response. If
a BEAT ACK is received, it shall be discarded and a report made to Layer Management.
Routing Key Management (RKM) Messages:
These messages shall not be sent. If a Routing Key Management message is received an Error (ERR) message shall be
returned with Error Code "Unsupported Message Class", the RKM message shall be discarded and a report made to
Layer Management.
Connection-Oriented messages:
Reset Confirm, Reset Request and Connection Oriented Data Acknowledge messages are not in the scope of the present
document.
Subsection 3.2.1 Connectionless Data Transfer (CLDT)
Message Priority is not required.
SS7 Hop Count should be used.
For protocol class 0 messages, the sending SUA layer shall take into account the loading of SCTP streams when setting
the Sequence Control parameter.
Note that if a Segmentation parameter is present and its first/remaining segments field indicates more than one segment,
the value of the Sequence Control parameter shall be the same (non-zero) value for all segments of the group (i.e. all
segments with the same Segmentation Reference value, Source and Destination Addresses).
Subsection 3.2.2 Connectionless Data Response (CLDR)
The CLDR message shall be used if a message is returned from the node itself (conveyed in an N-NOTICE indication
to SUA), in addition to its use when a node receives an (X)(L)UDTS message for onward transfer.
Subsection 3.3.1 Connection Oriented Data Transfer (CODT)
Message Priority is not required.
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"NOTE *1" does not apply.
DT2 and ED shall not be sent. If received they shall be discarded and a report made to Layer Management.
Subsection 3.3.2 Connection Oriented Data Acknowledge (CODA)
Does not apply.
Subsection 3.3.3 Connection Request (CORE)
Message Priority is not required.
SS7 Hop Count should be used.
Credit is not required.
Sequence number is not required.
If a CORE message is received with Protocol Class indicating class 3, and the node supports SCCP management
procedures and class 2 but not class 3, the class shall be lowered to 2 in the COAK message sent in reply (see
EN 300 009-1 [1], page 12 "Page 25, clause 3.1.3.1" and "Page 27, clause 3.1.5.1").
Subsection 3.3.4 Connection Acknowledge (COAK)
Message Priority is not required.
Credit is not required.
For actions on reception of a COAK message for protocol class other than 2, see EN 300 009-1 [1], page 12 "Page 26,
clause 3.1.4.2" and "Page 28, clause 3.1.5.2".
Subsection 3.3.8 Reset Request (RESRE)
Does not apply.
Subsection 3.3.9 Reset Confirm (RESCO)
Does not apply.
Subsection 3.3.11 Connection Oriented Inactivity Test (COIT)
Sequence Number is not required.
Credit is not required.
Subsection 3.4.1 Destination Unavailable (DUNA)
SMI is not required.
A DUNA message containing an SSN shall contain in the Affected Point Code parameter just one point code, that of the
destination containing the unavailable subsystem.
For DUNA messages not containing an SSN, it is optional to send an Affected Point Code parameter with more than
one point code in it, but the ability to receive such a parameter is mandatory. The SG may limit the frequency at which
it sends by the response method DUNAs referring to a particular destination, to 1 in the T8 interval of ITU-T
Recommendation Q.704 [6], to give the receiver time to react.
Subsection 3.4.2 Destination Available (DAVA)
SMI is not required.
A DAVA message containing an SSN shall contain in the Affected Point Code parameter just one point code, that of the
destination containing the available subsystem.
For DAVA messages not containing an SSN, it is optional to send an Affected Point Code para
...