ETSI TS 124 011 V16.0.0 (2020-07)

Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); LTE; 5G; Point-to-Point (PP) Short Message Service (SMS) support on mobile radio interface (3GPP TS 24.011 version 16.0.0 Release 16)

RTS/TSGC-0124011vg00

General Information

• Status: Not Published
• Technical Committee: 3GPP CT 1 - MM/CC/SM [lu] (formely CN1)
• Current Stage: 12 - Completion
• Completion Date: 28-Jul-2020

Standards Content (Sample)

TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
LTE;
5G;
Point-to-Point (PP) Short Message Service (SMS)
support on mobile radio interface
(3GPP TS 24.011 version 16.0.0 Release 16)

3GPP TS 24.011 version 16.0.0 Release 16 1 ETSI TS 124 011 V16.0.0 (2020-07)

Reference
RTS/TSGC-0124011vg00
Keywords
5G,GSM,LTE,UMTS
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ETSI
3GPP TS 24.011 version 16.0.0 Release 16 2 ETSI TS 124 011 V16.0.0 (2020-07)
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Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 7
1 Scope . 8
1.1 References . 8
1.2 Abbreviations . 9
2 Overview of Short Message Service (SMS) support . 9
2.1 Protocols and protocol architecture . 10
2.2 Use of channels (A/Gb mode only) . 12
2.3 Layer 2 SAPI 3 handling for circuit switched in A/Gb mode . 13
2.4 Layer 2 (LLC) GPRS support (A/Gb mode only) . 13
2.5 GSMS entity in Iu mode . 14
2.5A ESMS entity in S1 mode . 15
2.5B 5GSMS entity in N1 mode . 15
2.6 MS support for SMS over GPRS . 16
2.7 MS support for device triggering short message . 16
3 Service definition . 16
3.1 General . 16
3.2 Service provided by the CM-sublayer . 17
3.2.1 Definition of primitives on the MS side . 17
3.2.1.1 MNSMS-ABORT-REQuest . 17
3.2.1.2 MNSMS-DATA-REQuest . 18
3.2.1.3 MNSMS-DATA-INDication . 18
3.2.1.4 MNSMS-ESTablish-REQuest . 18
3.2.1.5 MNSMS-ESTablish-INDication . 18
3.2.1.6 MNSMS-ERROR-INDication . 18
3.2.1.7 MNSMS-RELease-REQuest . 18
3.2.2 Definition of primitives on the network side . 18
3.2.2.1 MNSMS-ABORT-REQuest . 19
3.2.2.2 MNSMS-DATA-REQuest . 19
3.2.2.3 MNSMS-DATA-INDication . 19
3.2.2.4 MNSMS-ESTablish-REQuest . 19
3.2.2.5 MNSMS-ESTablish-INDication . 19
3.2.2.6 MNSMS-ERROR-INDication . 20
3.2.2.7 MNSMS-RELease-REQuest . 20
3.3 Service provided by SM-RL . 20
3.3.1 Definition of primitives on the MS side . 20
3.3.1.1 SM-RL-DATA-REQuest . 20
3.3.1.2 SM-RL-DATA-INDication . 21
3.3.1.3 SM-RL-MEMORY-AVAILABLE-REQuest . 21
3.3.1.4 SM-RL-REPORT-REQest . 21
3.3.1.5 SM-RL-REPORT-INDication . 21
3.3.2 Definition of primitives on the network side . 21
3.3.2.1 SM-RL-DATA-REQuest . 22
3.3.2.2 SM-RL-DATA-INDication . 22
3.3.2.3 SM-RL-MEMORY-AVAILABLE-INDication . 22
3.3.2.4 SM-RL-REPORT-REQuest . 22
3.3.2.5 SM-RL-REPORT-INDication . 22
4 Void . 22
5 CM-procedures . 22
5.1 General . 22
5.2 Short Message Control states . 23
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5.2.1 SMC-CS states at the MS side of the radio interface . 23
5.2.1.1 Mobile Originating Case . 23
5.2.1.1.1 MO-Idle (State 0) . 23
5.2.1.1.2 MO-MM-connection pending (State 1) . 23
5.2.1.1.3 MO-Wait for CP-ACK (State 2) . 23
5.2.1.1.4 MO-MM-connection established (State 3) . 23
5.2.1.2 Mobile Terminating case . 23
5.2.1.2.1 MT-Idle (State 0) . 23
5.2.1.2.2 MT-Wait for CP-ACK (State 2) . 23
5.2.1.2.3 MT-MM-connection established (State 3) . 23
5.2.2 SMC-GP, SMC-EP and SMC-5G states at the MS side of the radio interface . 24
5.2.2.1 Mobile Originating Case . 24
5.2.2.1.1 MO-Idle (State 0) . 24
5.2.2.1.2 MO-GMM-connection pending (State 1) (Iu mode only) . 24
5.2.2.1.3 MO-Wait for CP-ACK (State 2) . 24
5.2.2.1.4 MO-Wait for CP-Data (State 3) . 24
5.2.2.1.5 MO-EMM-connection pending (State 4) (S1 mode only) . 24
5.2.2.2 Mobile Terminating case . 24
5.2.2.2.1 MT-Idle (State 0) . 24
5.2.2.2.2 MT-Wait for RP-ACK (State 1) . 24
5.2.2.2.3 MT-Wait for CP-ACK (State 2) . 24
5.2.3 SMC-CS states at the network side of the radio interface . 24
5.2.3.1 Mobile Originating Case . 24
5.2.3.1.1 MO-Idle (State 0) . 25
5.2.3.1.2 MO-Wait for CP-ACK (State 2) . 25
5.2.3.1.3 MO-MM-connection established (State 3) . 25
5.2.3.2 Mobile Terminating Case . 25
5.2.3.2.1 MT-Idle (State 0) . 25
5.2.3.2.2 MT-MM-connection pending (State 1) . 25
5.2.3.2.3 MT-Wait for CP-ACK (State 2) . 25
5.2.3.2.4 MT-MM-connection established (State 3) . 25
5.2.4 SMC-GP, SMC-EP and SMC-5G states at the network side of the radio interface . 25
5.2.4.1 Mobile Originating Case . 25
5.2.4.1.1 MO-Idle (State 0) . 25
5.2.4.1.2 MO-Wait for RP-ACK (State 1) . 26
5.2.4.1.3 MO-Wait for CP-ACK(State 2) . 26
5.2.4.2 Mobile Terminating Case . 26
5.2.4.2.1 MT-Idle (State 0) . 26
5.2.4.2.2 MT-Wait for CP-ACK (State 1) . 26
5.2.4.2.3 MT-Wait for CP DATA (State 2) . 26
5.3 Short Message Control procedures . 26
5.3.1 MM-connection establishment for circuit switched service . 26
5.3.2 RPDU transfer . 27
5.3.2.1 RPDU transfer for circuit switched service . 27
5.3.2.2 RPDU transfer for GPRS, EPS and 5GS . 27
5.3.3 Release of MM and CM connections . 29
5.3.4 Abnormal cases . 29
5.4 Concatenating short message or notification transfers . 30
6 SM-RL-procedures . 31
6.1 General . 31
6.2 Transition states of SMR entity . 31
6.2.1 SMR-states at the MS-side of the radio interface . 31
6.2.1.1 Idle (State 0) . 31
6.2.1.2 Wait for RP-ACK (State 1) . 32
6.2.1.2a Wait to send RP-ACK (State 3) . 32
6.2.1.3 Wait for RETRANS TIMER (State 4) . 32
6.2.2 SMR-states at the network side of the radio interface . 32
6.2.2.1 Idle (State 0) . 32
6.2.2.2 Wait for RP-ACK (State 1) . 32
6.2.2.3 Wait to send RP-ACK (State 3) . 32
6.3 Short Message Relay procedures . 32
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6.3.1 TPDU relaying . 32
6.3.2 [Void] . 33
6.3.3 Notification relaying . 33
6.3.3.1 MS side . 33
6.3.3.1.1 Idle state . 33
6.3.3.1.2 Wait for RP-ACK state . 33
6.3.3.1.3 Wait for RETRANS Timer state. 34
6.3.3.2 Network side . 34
6.3.3.2.1 Idle state . 34
6.3.3.2.2 Wait to Send RP-ACK state . 34
6.3.4 Abnormal cases . 35
7 Message functional definitions and content . 35
7.1 General . 35
7.2 Messages for short message or notification transfer on CM . 35
7.2.1 CP-DATA . 35
7.2.2 CP-ACK . 35
7.2.3 CP-ERROR . 36
7.3 Messages for short message and notification transfer on SM-RL . 36
7.3.1 RP-DATA . 36
7.3.1.1 RP-DATA (Network to Mobile Station) . 36
7.3.1.2 RP-DATA (Mobile Station to Network) . 36
7.3.2 RP-SMMA . 37
7.3.3 RP-ACK . 37
7.3.4 RP-ERROR . 37
8 Message format and information elements coding . 38
8.1 CP-messages . 38
8.1.1 General . 38
8.1.2 Protocol Discriminator and Transaction Identifier . 38
8.1.3 Message type . 38
8.1.4 Other required information elements . 38
8.1.4.1 CP-User data element . 38
8.1.4.2 CP-Cause element . 39
8.2 RP-messages . 39
8.2.1 General . 39
8.2.2 Message type indicator (MTI) . 40
8.2.3 Message reference. 40
8.2.4 Void . 40
8.2.5 Other required information elements . 40
8.2.5.1 Originator address element . 40
8.2.5.2 Destination address element . 41
8.2.5.3 RP-User data element . 42
8.2.5.4 RP-Cause element . 42
9 Handling of unknown, unforeseen, and erroneous protocol data . 44
9.1 General . 44
9.2 CP Error Handling . 44
9.2.1 Message too short . 45
9.2.2 Unknown or unforeseen transaction identifier . 45
9.2.3 Unknown or unforeseen message type. 45
9.2.4 Non-semantical mandatory information element errors. 45
9.2.5 Messages with semantically incorrect contents . 46
9.3 RP Error Handling . 46
9.3.1 Message too short . 46
9.3.2 Unknown or unforeseen Message Reference . 46
9.3.3 Unknown or unforeseen message type. 46
9.3.4 Non-semantical mandatory information element errors. 47
9.3.5 Messages with semantically incorrect contents . 47
10 Timers. 47
10.1 Timers when the MS is not using EPS services with control plane CIoT EPS optimization and not using
5GS services with control plane CIoT 5GS optimization. 47
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10.2 Timers when the MS is using EPS services with control plane CIoT EPS optimization or using 5GS
services with control plane CIoT 5GS optimizatio n . 47
Annex A (informative): Arrow diagrams . 49
Annex B (normative): SDL-description of the CM-layer . 60
B.1 Introduction . 60
Annex C (informative): Arrow diagrams . 121
Annex D (normative): SDL-description of the short message relay layer . 127
D.1 Introduction . 127
Annex E (informative): Cause definition. 135
Annex F (informative): LAPDm SAPI 3 handling for short message service . 140
Annex G (informative): Change history . 147
History . 150

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Foreword
rd
This Technical Specification (TS) has been produced by the 3 Generation Partnership Project (3GPP).
The present document defines the Short Message Service (SMS) support on mobile radio interface within the 3GPP
system.
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
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3GPP TS 24.011 version 16.0.0 Release 16 8 ETSI TS 124 011 V16.0.0 (2020-07)
1 Scope
The present document specifies the procedures used across the mobile radio interface by the signalling layer 3 function
Short Message Control (SMC) and Short Message Relay function (SM-RL) for circuit switched in A/Gb mode, GPRS,
EPS, and 5GS.
1.1 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. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] Void.
[1a] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 23.040: "Technical realization of the Short Message Service (SMS) Point-to-Point (PP)".
[3a] 3GPP TS 23.060: "General Packet Radio Service (GPRS); Service description; Stage 2".
[3] 3GPP TS 44.006: "Mobile Station - Base Station System (MS - BSS) interface; Data Link (DL)
layer specification".
[4] 3GPP TS 24.007: "Mobile radio interface signalling layer 3; General aspects".
[5] 3GPP TS 24.008: "Mobile radio interface layer 3 specification".
[5a] 3GPP TS 25.331: "Radio Resource Control (RRC); Protocol Specification".
[5b] 3GPP TS 33.102: "3G Security; Security Architecture".
[5c] 3GPP TS 42.017: "Subscriber Identity Modules (SIM); Functional characteristics".
[6a] 3GPP TS 44.064: "General Packet Radio Service (GPRS); Logical Link Control (LLC) layer
specification ".
[6] ISO 7498: "Information processing systems - Open Systems Interconnection - Basic Reference
Model".
[7] 3GPP TS 44.018: "Mobile radio interface layer 3 specification; Radio Resource Control Protocol".
[8] 3GPP TS 25.413: "UTRAN Iu interface RANAP signalling".
[9] 3GPP TS 23.401: "General Packet Radio Service (GPRS) enhancements for Evolved Universal
Terrestrial Radio Access Network (E-UTRAN) access"
[10] 3GPP TS 24.301: "Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS);
Stage 3"
[11] 3GPP TS 23.272: "Circuit Switched Fallback in Evolved Packet System; Stage 2"
[12] 3GPP TS 29.118: "Mobility Management Entity (MME) – Visitor Location Register (VLR) SGs
interface specification"
[13] 3GPP TS 23.501: " System Architecture for the 5G System; Stage 2".
[14] 3GPP TS 23.502: " Procedures for the 5G System; Stage 2".
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[15] 3GPP TS 24.501: "Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3".
[16] 3GPP TS 29.518: "5G System; Access and Mobility Management Services; Stage 3".
[17] 3GPP TS 29.540: "5G System; SMS Services; Stage 3".
1.2 Abbreviations
For the purpose of the present document, the abbreviations given in 3GPP TR 21.905 [1a] and the following apply:
RR connection: a RR connection is a dedicated physical circuit switched domain connection used by the two RR or
RRC peer entities to support the upper layers' exchange of information flows.
PS signalling connection: is a peer to peer UMTS connection between MS and CN packet domain node.
GPRS: Packet Services for GSM and UMTS system.
The label (A/Gb mode only): indicates this section or paragraph applies only to GSM system. For multi system case
this is determined by the current serving radio access network.
The label (Iu mode only): indicates this section or paragraph applies only to UMTS system. For multi system case
this is determined by the current serving radio access network.
The label (S1 mode only): indicates this section or paragraph applies only to Evolved Packet Core (EPC) and E-
UTRAN access. For multi system case this is determined by the current serving radio access
network.
In A/Gb mode,.: Indicates this paragraph applies only to GSM System. For multi system case this is determined
by the current serving radio access network.
In Iu mode,.: Indicates this paragraph applies only to UMTS System. For multi system case this is determined by
the current serving radio access network.
In S1 mode,.: Indicates this paragraph applies only to Evolved Packet Core and E-UTRAN access. For multi
system case this is determined by the current serving radio access network.
In N1 mode: Indicates this paragraph applies only to 5G core network and NG-RAN access. For multi system case
this is determined by the current serving radio access network.
SIM: Subscriber Identity Module (see 3GPP TS 42.017 [5c]). This specification makes no distinction between SIM
and USIM.
MS: Mobile Station. This specification makes no distinction between MS and UE.
For the purposes of the present document, the following terms and definitions given in 3GPP TS 24.301 [10] apply:
UE using EPS services with control plane CIoT EPS optimization
2 Overview of Short Message Service (SMS) support
The purpose of the Short Message Service is to provide the means to transfer messages between a GSM PLMN Mobile
Station (MS) and a Short Message Entity via a Service Centre, as described in 3GPP TS 23.040 [2]. The terms
"MO" - Mobile Originating - and "MT" - Mobile Terminating - are used to indicate the direction in which the short
message is sent.
The present document describes the procedures necessary to support the Short Message Service between the MS and the
MSC or SGSN or MME or SMSF and vice versa, as described in 3GPP TS 23.040 [2].
The procedures are based on services provided by the Mobility Management sublayer as described in
3GPP TS 24.007 [4]/3GPP TS 24.008 [5] for CS in A/Gb mode and CS/PS services in Iu mode, 3GPP 24.301 [10] for
CS/PS services in S1 mode, 3GPP TS 24.501 [15] for N1 mode and the Logical Link Control layer described in 3GPP
TS 44.064 [6a] for GPRS services. For CS/PS service in S1 mode, depending on network configuration and UE
subscription data, network may choose to use either packet-switched service or circuit-switched service to provide SMS
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service. If circuit-switched service is used instead of packet-switched service, then the messages are tunneled through
the MME. In this case the network also uses procedures described in 3GPP 29.118 [12].
2.1 Protocols and protocol architecture
In Iu mode only, integrity protected signalling (see 3GPP TS 24.008 [5], subclause 'Integrity Protection of Signalling
Messages' and in general, see 3GPP TS 33.102 [5b]) is mandatory. In Iu mode only, all protocols shall use integrity
protected signalling. Integrity protection of all SMS signalling messages is the responsibility of lower layers. It is the
network which activates integrity protection. This is done using the security mode control procedure
(3GPP TS 25.331 [5a]).
The hierarchical model in figure 2.1a shows the layer structure of the MSC and the MS in A/Gb mode. The hierarchical
model in figure 2.1c shows the layer structure of the SGSN and the MS in Iu mode. The hierarchical model in
figure 2.1d shows the layer structure of the MSC and the MS in S1 mode. The hierarchical model in figure 2.1e shows
the layer structure of the MME and the MS in S1 mode.

MSC  MS
SM-AL
SM-TL
SM-RL  SMR <⎯⎯⎯⎯⎯⎯ SM-RP protocol ⎯⎯⎯⎯⎯> SMR

CM-sublayer  SMC  SMC
<⎯⎯⎯⎯⎯⎯ SM-CP protocol ⎯⎯⎯⎯⎯>
MM-sublayer
RR-sublayer
Figure 2.1a/3GPP TS 24.011: Protocol hierarchy for circuit-switched service
The hierarchical model in figure 2.1b shows the layer structure of the SGSN and the MS in A/Gb mode.

SGSN  MS
SM-AL
SM-TL
SM-RL  SMR  SMR
<⎯⎯⎯⎯⎯⎯ SM-RP protocol ⎯⎯⎯⎯⎯>
CM-sublayer  SMC  SMC
<⎯⎯⎯⎯⎯⎯ SM-CP protocol ⎯⎯⎯⎯⎯>
LLC-sublayer
GRR-sublayer
Figure 2.1b/3GPP TS 24.011: Protocol hierarchy for GPRS in A/Gb mode
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SGSN  MS
SM-AL
SM-TL
SM-RL
SMR <⎯⎯⎯⎯⎯⎯ SM-RP protocol ⎯⎯⎯⎯⎯> SMR
CM-sublayer
SMC <⎯⎯⎯⎯⎯⎯ SM-CP protocol ⎯⎯⎯⎯⎯> SMC
GMM-sublayer
Figure 2.1c/3GPP TS 24.011: Protocol hierarchy for packet-switched service in Iu mode
MSC  MS
SM-AL     SM-AL
SM-TL     SM-TL
SM-RL  SMR  SMR SM-RL
<⎯⎯⎯ SM-RP protocol ⎯⎯⎯>
CM-sublayer  SMC  SMC CM-sublayer
<⎯⎯⎯⎯ SM-CP protocol ⎯⎯⎯>
SGs layer     EMM-sublayer

NOTE: SM-CP messages are transferred between the MSC and the MS through the MME. The protocol stack on
the MME is not shown.
Figure 2.1d/3GPP TS 24.011: Protocol hierarchy for circuit-switched service in S1 mode
MME  MS
SM-AL
SM-TL
SM-RL
SMR <⎯⎯⎯⎯⎯⎯ SM-RP protocol ⎯⎯⎯⎯⎯> SMR
CM-sublayer
SMC  SMC
<⎯⎯⎯⎯⎯⎯ SM-CP protocol ⎯⎯⎯⎯⎯>
EMM-sublayer
Figure 2.1e/3GPP TS 24.011: Protocol hierarchy for packet-switched service in S1 mode
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SMSF  MS
SM-AL     SM-AL
SM-TL     SM-TL
SM-RL  SMR  SMR SM-RL
<⎯⎯⎯ SM-RP protocol ⎯⎯⎯>
CM-sublayer  SMC <⎯⎯⎯⎯ SM-CP protocol ⎯⎯⎯> SMC CM-sublayer

N20-layer     5GMM-sublayer

NOTE: SM-CP messages are transferred between the SMSF and the MS through the AMF. The protocol stack on
the AMF is not shown.
Figure 2.1f/3GPP TS 24.011: Protocol hierarchy in N1 mode
The CM-sublayer, in terms of the Short Message Service Support, provides services to the Short Message Relay Layer.
On the MS-side the Short Message Relay Layer provides services to the Short Message Transfer Layer. The Short
Message
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