SIST ES 202 060-3 V1.1.1:2005

Short Message Service (SMS) for fixed networks; Network Based Solution (NBS); Part 3: Integrated Services Digital Network (ISDN) access protocol

The purpose of this standard is to define a Network Based Solution (NBS) protocol for a Short Message Service (SMS) delivered on an ISDN access, based on SPAN11's deliverable DES/SPAN-110093 (ES 201 986).

Storitev kratkih sporočil (SMS) za fiksna omrežja – Omrežna rešitev (NBS) – 3. del: Dostopovni protokol digitalnega omrežja z integriranimi storitvami (ISDN)

General Information

• Status: Published
• Publication Date: 31-Dec-2004
• ICS: 33.040.35 - Telephone networks
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SPN - Services and Protocols for Networks
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Jan-2005
• Due Date: 01-Jan-2005
• Completion Date: 01-Jan-2005
• Ref Project: ETSI ES 202 060-3 V1.1.1 (2003-05) - Short Message Service (SMS) for fixed networks; Network Based Solution (NBS); Part 3: Integrated Services Digital Network (ISDN) access protocol

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ES 202 060-3 V1.1.1:2005
01-januar-2005
6WRULWHYNUDWNLKVSRURþLO606]DILNVQDRPUHåMD±2PUHåQDUHãLWHY1%6±GHO
'RVWRSRYQLSURWRNROGLJLWDOQHJDRPUHåMD]LQWHJULUDQLPLVWRULWYDPL,6'1
Short Message Service (SMS) for fixed networks; Network Based Solution (NBS); Part 3:
Integrated Services Digital Network (ISDN) access protocol
Ta slovenski standard je istoveten z: ES 202 060-3 Version 1.1.1
ICS:
33.040.35 Telefonska omrežja Telephone networks
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
SIST ES 202 060-3 V1.1.1:2005 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST ES 202 060-3 V1.1.1:2005

---------------------- Page: 2 ----------------------

SIST ES 202 060-3 V1.1.1:2005

ETSI ES 202 060-3 V1.1.1 (2003-05)
ETSI Standard


Short Message Service (SMS) for fixed networks;
Network Based Solution (NBS);
Part 3: Integrated Services Digital Network (ISDN)
access protocol

---------------------- Page: 3 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 2 ETSI ES 202 060-3 V1.1.1 (2003-05)



Reference
DES/SPAN-130286
Keywords
ISDN, DSS1, SMS, functional, protocol
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: [phone]  Fax: [phone]

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org
The present document may be made available in more than one electronic version or in print. In any case of existing or
perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).
In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive
within ETSI Secretariat.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
http://portal.etsi.org/tb/status/status.asp
If you find errors in the present document, send your comment to:
[e-mail]
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 2003.
All rights reserved.

TM TM TM
DECT , PLUGTESTS and UMTS are Trade Marks of ETSI registered for the benefit of its Members.
TM
TIPHON and the TIPHON logo are Trade Marks currently being registered by ETSI for the benefit of its Members.
TM
3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.
ETSI

---------------------- Page: 4 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 3 ETSI ES 202 060-3 V1.1.1 (2003-05)
Contents
Intellectual Property Rights.4
Foreword.4
Introduction .4
1 Scope.5
2 References.5
3 Definitions and abbreviations.6
3.1 Definitions.6
3.2 Abbreviations.7
4 Description.8
5 Operational requirements.9
5.1 Provision and withdrawal.9
5.2 Requirements on the receiving user's network side.9
5.3 Requirements on the controlling user's network side .9
6 Coding requirements.10
7 Signalling procedures at the coincident S and T reference point .13
7.1 Registration.13
7.2 Activation of the SMS at the originating user's interface .13
7.3 Deactivation of the SMS at the originating user's interface.13
7.4 Deactivation of the reception of SMs .13
7.5 Invocation of SMS at the originating user's interface.13
7.5.1 Normal operation.13
7.5.2 Exceptional procedure.14
7.6 Invocation of SMS at the receiving user's interface .15
7.6.1 Normal operation.15
7.6.2 Exceptional procedure.15
7.7 Interrogation.16
8 Procedures for interworking with private ISDNs.16
9 Interactions with other networks .16
10 Interactions with supplementary services.16
11 Parameter values (timers).16
Annex A (informative): Signalling flows .17
Annex B (informative): Structure of the SMS information in DSS1 .23
Annex C (informative): Assignment of object identifier values .24
Annex D (informative): Bibliography.25
History .26

ETSI

---------------------- Page: 5 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 4 ETSI ES 202 060-3 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 ETSI Standard (ES) has been produced by ETSI Technical Committee Services and Protocols for Advanced
Networks (SPAN).
The present document is part 3 of a multi-part standard covering the Short Message Services (SMS) for fixed networks;
Networks Based Solution (NBS), as described below:
Part 1: "Overview";
Part 2: "Architecture and functional entities";
Part 3: "Integrated Services Digital Network (ISDN) access protocol";
Part 4: "Interworking between Signalling System No.7 (SS7) and Digital Subscriber Signalling System No. one
(DSS1)";
Part 5: "Network access protocol".
NOTE: The choice of a multi-part format for this deliverable is to facilitate maintenance and future
enhancements.
In accordance with ITU-T Recommendation I.130 [4], the following three level structure is used to describe the
supplementary telecommunication services as provided by European public telecommunications operators under the
pan-European ISDN:
• Stage 1 is an overall service description, from the user's standpoint;
• Stage 2 identifies the functional capabilities and information flows needed to support the service described in
stage 1; and
• Stage 3 defines the signalling system protocols and switching functions needed to implement the service
described in stage 1.
The present document details the stage 3 aspects (signalling system protocols and switching functions) needed to
support the SM service. The stage 1 aspects are detailed in ES 201 986 [10]. The stage 2 aspects of the SM service have
not been specified.
The present version updates the references to the basic call specifications.
Introduction
The Short Message Service (SMS) is a service, applicable at the coincident S and T reference point and T reference
point, to provide the served user the ability to send and receive Short Messages. The Short Messages (SM) are
exchanged between the sending and receiving user via a Short Message Service Centre (SM-SC).
ETSI

---------------------- Page: 6 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 5 ETSI ES 202 060-3 V1.1.1 (2003-05)
1 Scope
The present document specifies the stage three of the Short Message Service (SMS) for the pan-European Integrated
Services Digital Network (ISDN) as provided by European public telecommunications operators at the T reference
point or coincident S and T reference point (as defined in ITU-T Recommendation I.411 [6]) by means of the Digital
Subscriber Signalling System No. one (DSS1) protocol. Stage three identifies the protocol procedures and switching
functions needed to support a telecommunication service (see ITU-T Recommendation I.130 [4]).
In addition, the present document specifies the protocol requirements at the T reference point where the service is
provided to the user via an intermediate private ISDN.
The present document does not specify the additional protocol requirements where the service is provided to the user
via a telecommunication network that is not an ISDN but it does include interworking requirements of other networks
with the public ISDN.
The SM service is provided independently of a call.
Charging principles are outside the scope of the present document.
The SM service enables the originating SMS user to send Short Messages (SMs) to the receiving SMS user via a Short
Message Service Centre (SM-SC), belonging to the network of the SMS originating user (served user) or separated
from the network of the SM originating user.
NOTE: The SM service is typically used between a Short Message service provider and a user (receiving user) of
the Short Message service provided.
Further parts of the present document specify the method of testing required to identify conformance to the present
document.
The present document is applicable to equipment supporting the SM service, to be attached at either side of a
T reference point or coincident S and T reference point when used as an access to the public ISDN.
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 300 196-1: "Integrated Services Digital Network (ISDN); Generic functional protocol for
the support of supplementary services; Digital Subscriber Signalling System No. one (DSS1)
protocol; Part 1: Protocol specification".
[2] ITU-T Recommendation E.164: "The international public telecommunication numbering plan".
[3] ITU-T Recommendation I.112: "Vocabulary of terms for ISDNs".
[4] ITU-T Recommendation I.130 (1988): "Method for the characterization of telecommunication
services supported by an ISDN and network capabilities of an ISDN".
[5] ITU-T Recommendation I.210: "Principles of telecommunication services supported by an ISDN
and the means to describe them".
[6] ITU-T Recommendation I.411 (1993): "ISDN user-network interfaces - Reference configurations".
ETSI

---------------------- Page: 7 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 6 ETSI ES 202 060-3 V1.1.1 (2003-05)
[7] ITU-T Recommendation Q.9 (1988): "Vocabulary of switching and signalling terms".
[8] ITU-T Recommendation X.680: "Information technology - Abstract Syntax Notation One
(ASN.1): Specification of basic notation".
[9] ITU-T Recommendation X.880: "Information technology - Remote Operations: Concepts, model
and notation".
[10] ETSI ES 201 986 (2001-11): "Services and Protocols for Advanced Networks (SPAN); Short
Message Service (SMS) for PSTN/ISDN; Service description".
[11] ETSI TS 123 040 (V5.3.0): "Digital cellular telecommunications system (GSM);Universal Mobile
Telecommunications System (UMTS);Technical realization of the Short Message Service (SMS)
(3GPP TS 23.040 version 5.3.0 Release 5)".
[12] ETSI ES 201 912: "Access and Terminals (AT); Short Message Service (SMS) for PSTN/ISDN;
Short Message Communication between a fixed network Short Message Terminal Equipment and
a Short Message Service Centre".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
basic access: See ITU-T Recommendation Q.9 [7].
basic call procedures: procedures by which a call (as an instance of a telecommunications service) is established and
terminated
delivery report: response from the destination terminal to the SM-SC indicating that an SM has been accepted or not
with the appropriate cause, if rejected
Integrated Services Digital Network (ISDN): See ITU-T Recommendation I.112 [3].
ISDN number: number conforming to the numbering plan and structure specified in ITU-T Recommendation E.164
invoke component: where reference is made to a "xxxx" invoke component, an invoke component is meant with its
operation value set to the value of the operation "xxxx"
NOTE: See EN 300 196-1 [1], clause 8.2.2.1.
network: DSS1 protocol entity at the network side of the user-network interface
originating SMS user: user that originates and sends the SM, also called the served user
primary rate access: See ITU-T Recommendation Q.9 [7].
private network: DSS1 protocol entity at the user side of the user-network interface at the T reference point
public network: DSS1 protocol entity at the network side of the user-network interface at the T reference point
receiving SMS user (destination SMS user): the user that receives the Short Message and who may also deactivate
the reception of SMs and reactivate the reception later on
receiving user number: ISDN number of the user, that receives the Short Message
reject component: See EN 300 196-1 [1], clause 8.2.2.4.
ETSI

---------------------- Page: 8 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 7 ETSI ES 202 060-3 V1.1.1 (2003-05)
reply path procedure: mechanism which allows an SM-TE to request that an SM-SC should be permitted to handle a
reply sent in response to a message previously sent from that SM-TE to another SM-TE
NOTE: This may happen even though the SM-SC may be unknown to the SM-TE which received the initial
message.
return error component: where reference is made to a "xxxx" return error component, a return error component is
meant which is related to a "xxxx" invoke component
NOTE: See EN 300 196-1 [1], clause 8.2.2.3.
return result component: where reference is made to a "xxxx" return result component, a return result component is
meant which is related to a "xxxx" invoke component
NOTE: See EN 300 196-1 [1], clause 8.2.2.2.
served user: user to whom the SMS is provided, also called the originating user
served user number: ISDN number of the user who subscribes to, activates, deactivates or interrogates the Short
Message services
service/telecommunication service: See ITU-T Recommendation I.112 [3].
Short Message (SM): information, that may be conveyed by means of the SMS described in the present document
Short Message Service Centre (SM-SC): function unit, which is responsible for the relaying and store-and-forwarding
of a short message (SM) between two SM-TE
NOTE: The SM-SC can functionally be separated from or integrated in the network.
Short Message Service Centre Number (SM-SCNr): ISDN number of the Short Message Service Centre
Short Message Terminal (SM-TE): terminal which may send or receive short messages
Status Report: information used to inform the originating SM-TE of the status of a short message previously submitted
by this SM-TE
EXAMPLE: whether the SM-SC was able to successfully forward the message or not, or whether the message
was stored in the SM-SC for later delivery.
submit report: response from the SM-SC to the originating terminal indicating that an SM has been accepted or not
with the appropriate cause, if rejected
supplementary service: See ITU-T Recommendation I.210 [5], clause 2.4.
user: DSS1 protocol entity at the user side of the user-network interface
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ASE Application Service Element
ASN.1 Abstract Syntax Notation One
DSS1 Digital Subscriber Signalling System No. one
DLL Data Link Layer
ISDN Integrated Services Digital Network
PDU Protocol Data Unit
PL Physical Layer
PIN Personal Identification Number
RL Relay Layer
SDL Specification and Description Language
SM Short Message
SMs Short Messages
SMS Short Message Service
SM-SC Short Message Service Centre
ETSI

---------------------- Page: 9 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 8 ETSI ES 202 060-3 V1.1.1 (2003-05)
SM-TE Short Message Terminal
TL Transport Layer
4 Description
The Short Message Service (SM) service shall be available to users who are connected to the network via a basic access
or primary rate access.
The Short Message Service (SMS) enables an originating user to send a SM of a limited size to a destination user.
A Short Message (SM) can be initiated upon a request of the sending user or by the service provider itself, and shall be
sent to the receiving user. An SM is always conveyed via an SM-SC. The SM-SC receives the SM from an originating
SM-TE (sending user), converts the message if necessary, and relays the SM to the terminating SM-TE (receiving user).
Network
Time
SM-SC
Local Exchange Local Exchange
SMSSubmit invoke
SMSSubmit return result
SMSDeliver invoke
Sending user
SMSDeliver return result
SMSDeliver invoke
Receiving user
Deliver return result

Figure 1: SMS submission, delivery and confirmation
A submit report is sent from an SM-SC to an SM-TE within a sMSSubmit return result component and may be either a
positive report, which confirms the correct submission of an SM to the SM-SC, or a negative report, which informs the
SM-TE that the SM was not successfully submitted with the error reason.
A deliver report is sent to an SM-SC within a sMSDeliver return result and may be either a positive report, which
confirms the correct delivery of an SM to the receiving SM-TE, or a negative report, which informs the SM-SC that the
SM was not successfully delivered with the error reason.
If the option to provide a status report is invoked and supported, a status report is sent from the SM-SC to the
originating SM-TE in a sMSDeliver invoke component; the SM-TE acknowledges correct receipt of the status report.
Having received one or more SMs, the receiving user can subsequently read, store or delete the messages on its
terminal. If the SM-TE supports the optional Replace Short Message Function, Short Messages (SMs) with the
respective Replace Short Message Type indication held in the SM-TE are automatically replaced by received new ones.
The means by which the receiving user manages these features are outside the scope of the present document.
The preparation of an SM as well as the kind of data transmission between the sending or receiving users and the
SM-SC are outside the scope of the present document.
ETSI

---------------------- Page: 10 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 9 ETSI ES 202 060-3 V1.1.1 (2003-05)
5 Operational requirements
5.1 Provision and withdrawal
The SMS shall be provided to the service provider (SM-SC) after prior arrangement with the network operator.
The SMS shall be withdrawn on the service provider's (SM-SC) request or for network operator reasons.
The SMS shall be provided to the SMS user after prior arrangement with the network operator and/or the service
provider or be generally available.
The SMS shall be withdrawn on the SMS user's request or for network operator or service provider (SM-SC) reasons.
Provision of the SMS shall be on a number basis.
The SM service shall apply to the basic access and to the primary rate access.
As a network operator option, the SMS user can have a subscription option to register the SM-SC number to which
outgoing messages shall be sent to.
The maximum number of SM-SC numbers from which incoming messages shall be accepted is a network operator
option.
Table 1 contains the network and service provider options for SMS.
Table 1: Network options/service provider options
Network options Values Network Service Provider
option option
Support of subscription option for registration of the SM-SC yes X
number to which outgoing messages shall be sent no
Maximum number of SM-SC numbers from which incoming any integer value X
messages shall be accepted
Registration and erasure procedure for the SM-originating yes X
user no
Registration and erasure procedure for the SM-receiving yes X
user no
PIN required for registration and erasure procedure yes X
no
Activation/deactivation of the receipt of SM yes X
no
PIN required for activation/deactivation procedure yes X
no
Interrogation of SM service, whether the yes X
service is activated or deactivated no

5.2 Requirements on the receiving user's network side
Void.
5.3 Requirements on the controlling user's network side
Void.
ETSI

---------------------- Page: 11 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 10 ETSI ES 202 060-3 V1.1.1 (2003-05)
6 Coding requirements
The SM-TL PDUs according to TS 123 040 [11] are transported transparently within a SMS-ASE in sMSSubmit and
sMSDeliver invoke components and return result components (all the SMS commands are transported transparently in
the Data component within the SMSSubmit and SMSDeliver components).

GSM DSS1
SMS protocol stack SMS protocol stack
Application Layer
Application Layer
TL (GSM 3.40)
TL (GSM 3.40)
RL (GSM 3.40) SMS-ASE
PLMN
specific
PSTN/ISDN
Lower Layers DLL

specific

PL


Figure 2: Relationship between SMS protocol stack in GSM and transport in DSS1
Table 2 shows the definitions of the operations and errors required for the SM service using ASN.1 as specified in
ITU-T Recommendation X.680 [8] and using the OPERATION and ERROR macros as defined in figure 4 of
ITU-T Recommendation X.880 [9].
The formal definition of the component types to encode these operations and errors is provided in clause D.1 of
EN 300 196-1 [1].
The inclusion of components in facility information elements is defined in EN 300 196-1 [1], clause 11.2.2.1.
All components (invoke, return result, return error and reject) shall be included within a facility information element.
This facility information element may be included in any appropriate message as specified in EN 300 196-1 [1],
clause 8.3.1.1, unless a more restrictive specification is given in clause 7 of the present document.
Table 2: Definition of operations and errors for the SMservice
SMS-Operations-and-Errors { itu-t identified-organization etsi(0) xxx operations-and-errors(1)}

DEFINITIONS EXPLICIT TAGS EXTENSIBILITY IMPLIED::=

BEGIN

EXPORTS

  SMSSubmit,
  SMSDeliver,

  InvalidSM_SCNr,
  SMSRejected,
  NotInvoked,
  IndicationNotDelivered

;
IMPORTS Code, ERROR, OPERATION,

  FROM Remote-Operation-Notation
  {joint-iso-itu-t remote-operations(4) notation(0)}

  notSubscribed,
  resourceUnavailable,
  invalidServedUserNr
  FROM General-Errors
  { itu-t identified-organization etsi(0) 196 general-errors(2)}

  invalidReceivingUserNr
ETSI

---------------------- Page: 12 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 11 ETSI ES 202 060-3 V1.1.1 (2003-05)
  FROM MWI-Operations-and-Errors
  { itu-t identified-organization etsi(0) 745 operations-and-errors(1)}

  PresentedNumberScreened,
  PartyNumber
  FROM Addressing-Data-Element
  {itu-t identified-organization etsi(0) 196 addressing-data-elements(6)}
;

sMSSubmit OPERATION ::{
   ARGUMENT SMS-Submit-Argument
   RESULT  SMS-Submit-Result
   ERRORS  {SMS-Submit-Failure}
   CODE  sMS-Submit-Code
}
-- End of SMSSubmit operation definition


SMS-Submit-Argument ::=SEQUENCE {
   servedUserNr   PresentedNumberScreened,
   receivingUserNr   PartyNumber,
   sMSData    SMSData,
       -- SMSData contains one of the following
       -- TL messages: SMS_SUBMIT, SMS_COMMAND
   sM_SCNr   [1] PartyNumber  OPTIONAL,
   additions   [2] Additions  OPTIONAL}

SMS-Submit-Result ::=SEQUENCE {
   servedUserNr   PresentedNumberScreened,

       -- In the SMS-Submit-Result, either a
       -- positive (sMSAck) or negative
        -- confirmation (sMSNack) is present
   sMS-POS-NEG-CONF  CHOICE {
    sMSAck    SMSAck,
       -- SMSAck contains a positive
       -- SMS_SUBMIT_REPORT
    sMSNack    SMSNack,
       -- SMSNack contains a negative
       -- SMS SUBMIT REPORT
   }
   additions   [1] Additions  OPTIONAL,
   sM_SCNr   [2] PartyNumber OPTIONAL }

sMS-Submit-Failure   ERROR ::={
PARAMETER   TypeOf_SubmitError
CODE    sMS-Submit-FailureCode
}

TypeOf_SubmitError  ::= ENUMERATED {
     notSubscribed  (0),
     resourceUnavailable (1),
     invalidServedUserNr (2),
     invalidReceivingUserNr (3),
     invalidSM_SCNr  (4),
     indicationNotDelivered (5),
     sMSRejected  (6)
}



sMSDeliver  OPERATION ::={
   ARGUMENT SMS-Deliver-Argument
   RESULT  SMS-Deliver-Result
   ERRORS  {sMS-Deliver-Failure}
   CODE  sMS-Deliver-Code
}
-- End of SMSDeliver operation definition


SMS-Deliver-Argument ::=SEQUENCE {
     servedUserNr PresentedNumberScreened,
     receivingUserNr PartyNumber,
     sM_SCNr  [1] PartyNumber OPTIONAL,
     additions [2] Additions OPTIONAL,
     sMSData  SMSData
     --sMSData contains one of the following
     -- TL messages: SMS_DELIVER, SMS_STATUS_REPORT
ETSI

---------------------- Page: 13 ----------------------

SIST ES 202 060-3 V1.1.1:2005
 12 ETSI ES 202 060-3 V1.1.1 (2003-05)
     }
SMS-Deliver-Result  ::=SEQUENCE {
     sM_SCNr  PartyNumber,

    sMS-POS-NEG-CONF CHOICE {
     sMSAck   SMSAck
        -- SMSAck contains a positive
        -- SMS-Deliver-Report
     sMSNack   SMSNack
        -- SMSNack contains a negative
        -- SMS-Deliver-Report
     }
     additions  Additions OP
...