ETSI TR 143 902 V13.0.0 (2016-01)

ETSI TR 1143 902 V13.0.0 (201616-01)






TECHNICAL REPORT
Digital cellular telecocommunications system (Phahase 2+);
Enhanced Genericic Access Networks (EGAN) s) study
(3GPP TR 43.9.902 version 13.0.0 Release 13 13)

R
GLOBAL SYSTTEME FOR
MOBILE COMMUUNNICATIONS

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3GPP TR 43.902 version 13.0.0 Release 13 1 ETSI TR 143 902 V13.0.0 (2016-01)



Reference
RTR/TSGG-0143902vd00
Keywords
GSM
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3GPP TR 43.902 version 13.0.0 Release 13 2 ETSI TR 143 902 V13.0.0 (2016-01)
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 (https://ipr.etsi.org/).
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 ETSI 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 Technical Report (TR) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or
GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables.
The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under
http://webapp.etsi.org/key/queryform.asp.
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TR 43.902 version 13.0.0 Release 13 3 ETSI TR 143 902 V13.0.0 (2016-01)
Contents
Intellectual Property Rights . 2
Foreword . 2
Modal verbs terminology . 2
Foreword . 6
Introduction . 6
1 Scope . 7
2 References . 7
3 Definitions, symbols and abbreviations . 8
3.1 Definitions . 8
3.2 Symbols . 8
3.3 Abbreviations . 8
4 Requirements . 10
4.1 Objectives . 10
4.2 Benefits . 11
4.3 For further investigation . 11
5 Architecture alternatives. 11
5.1 A/Gn based architectures . 11
5.1.1 Enhanced Up . 11
5.1.1.1 Architecture . 11
5.1.1.2 Protocol stacks . 13
5.1.1.2.1 PS Control Plane. 13
5.1.1.2.2 PS User Plane . 14
5.1.1.3 Affected Procedures . 14
5.1.1.3.1 PS mobility overview . 14
5.1.1.3.2 PDP Context Activation /De-Activation . 20
5.1.1.3.3 PS Handover procedures between GAN and GERAN/UTRAN . 26
5.1.1.3.4 CS+PS Handover between GAN and GERAN/UTRAN . 29
5.1.1.3.5 APN resolution in EGAN mode . 35
5.1.1.3.6 SMS in EGAN mode . 38
5.1.1.3.7 EGAN Registration and subscriber management in PS Domain . 39
5.1.1.3.8 Network Requested PDP Context Activation (NRPCA) . 42
5.1.1.3.9 Roaming aspects . 45
5.1.1.4 Terminal architecture and impacts . 46
5.1.1.4.1 Introduction . 46
5.1.1.4.2 CS domain Control Plane . 47
5.1.1.4.3 CS domain User Plane . 48
5.1.1.4.4 PS domain. 48
5.1.1.5 EGAN handovers and LA/RA Update signalling . 51
5.1.1.5.1 Introduction . 51
5.1.1.5.2 GERAN/GAN Scenario . 51
5.1.1.5.3 UMTS/GERAN/GAN Scenario . 53
5.1.1.5.4 GAN Enhancement alternatives . 53
5.1.1.6 Proxy-Gn Load and Performance . 54
5.1.1.6.1 Introduction . 54
5.1.1.6.2 Assumptions . 55
5.1.1.6.3 CPU Load . 55
5.1.1.6.4 Memory Consumption . 56
5.1.1.6.5 Signalling Delay . 56
5.1.2 Combined GANC/SGSN . 57
5.1.2.1 Introduction . 57
5.1.2.2 Architecture . 58
ETSI

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3GPP TR 43.902 version 13.0.0 Release 13 4 ETSI TR 143 902 V13.0.0 (2016-01)
5.1.2.3 Protocol stacks . 59
5.1.2.3.1 PS Control plane . 59
5.1.2.3.2 PS User plane . 60
5.1.2.4 Affected procedures . 60
5.1.2.5 Terminal architecture and impacts . 60
5.1.2.6 Optimization for LLC and SNDCP Layers . 61
5.2 GAN Iu Mode . 62
5.2.1 Functional Architecture . 62
5.2.2 Functional entities . 64
5.2.2.1 Mobile Station (MS) . 64
5.2.2.2 Generic Access Network Controller (GANC) . 64
5.2.3 Control and User Plane Architecture . 64
5.2.3.1 Circuit Switched (CS) Domain . 65
5.2.3.1.1 CS Domain - Control Plane . 65
5.2.3.1.2 CS Domain - User Plane . 66
5.2.3.2 Packet Switched (PS) Domain . 67
5.2.3.2.1 PS Domain - Control Plane . 67
5.2.3.2.2 PS Domain - User Plane . 68
5.2.3.3 GA-RC (Generic Access Resource Control) . 68
5.2.3.3.1 General . 68
5.2.3.3.2 States of the GA-RC sub-layer . 69
5.2.3.4 GA-RRC (Generic Access Radio Resource Control) . 70
5.2.3.4.1 General . 70
5.2.3.4.2 States of the GA-RRC sub-layer . 70
5.2.4 Security Mechanisms . 71
5.2.5 High Level Procedures . 71
5.2.5.1 Mode Selection in Multi-mode terminals . 71
5.2.5.2 PLMN Selection . 72
5.2.5.3 Re-selection between GERAN/UTRAN and GAN modes . 73
5.2.5.3.1 Rove-in (from GERAN/UTRAN mode to GAN mode) . 73
5.2.5.3.2 Rove-out (from GAN mode to GERAN/UTRAN mode) . 73
5.2.5.4 GAN Discovery and Registration related procedures . 74
5.2.5.4.1 Discovery and Registration for Generic Access . 74
5.2.5.4.2 De-Registration. 80
5.2.5.4.3 Registration Update . 81
5.2.5.4.4 Keep Alive . 82
5.2.5.4.5 Cell Broadcast Information . 82
5.2.5.5 Void. 83
5.2.5.6 Void. 83
5.2.5.7 GA-RRC Connection handling . 83
5.2.5.7.1 GA-RRC Connection Establishment . 83
5.2.5.7.2 GA-RRC Connection Release . 83
5.2.5.8 Security Mode Control . 84
5.2.5.9 NAS Signalling Procedures . 84
5.2.5.10 Mobile Originated CS Call . 85
5.2.5.11 Mobile Terminated CS Call . 87
5.2.5.12 CS Call Clearing . 88
5.2.5.13 CS Handover . 88
5.2.5.13.1 CS Handover from GERAN to GAN . 88
5.2.5.13.2 CS Handover from UTRAN to GAN . 90
5.2.5.13.3 CS Handover from GAN to GERAN . 92
5.2.5.13.4 CS Handover from GAN to UTRAN . 93
5.2.5.14 Void. 95
5.2.5.15 Void. 95
5.2.5.16 Void. 95
5.2.5.17 GA-RRC Packet Transport Channel Management Procedures . 95
5.2.5.17.1 States of the GA-RRC Packet Transport Channel . 96
5.2.5.17.2 PTC Initial Activation . 97
5.2.5.17.3 PTC Data Transfer . 98
5.2.5.17.4 MS initiated PTC Deactivatio n . 99
5.2.5.17.5 MS initiated PTC Re-activation . 100
5.2.5.17.6 Network initiated PTC De-activation . 101
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3GPP TR 43.902 version 13.0.0 Release 13 5 ETSI TR 143 902 V13.0.0 (2016-01)
5.2.5.17.7 Network initiated PTC Re-activation . 101
5.2.5.17.8 Implicit PTC De-activation due to MS De-registration . 102
5.2.5.18 PDP Context Activation . 103
5.2.5.19 Network Requested PDP Context Activation. 104
5.2.5.20 PS Handover between GERAN and GAN . 105
5.2.5.20.1 PS Handover from GERAN to GAN . 105
5.2.5.20.2 PS Handover from GAN to GERAN . 105
5.2.5.21 SRNS Relocation between UTRAN and GAN . 105
5.2.5.21.1 SRNS Relocation from UTRAN to GAN . 105
5.2.5.21.2 SRNS Relocation from GAN to UTRAN . 107
5.2.6 Terminal Architecture Impacts . 109
5.2.6.1 Assumptions and Definitions . 109
5.2.6.2 Impact on CS Control Plane . 110
5.2.6.2.1 CS Control Plane - Before . 110
5.2.6.2.2 CS Control Plane-After . 111
5.2.6.2.3 Summary of CS Control Plane Changes . 111
5.2.6.3 Impact on CS User Plane . 112
5.2.6.3.1 CS User Plane-Before . 112
5.2.6.3.2 CS User Plane-After . 113
5.2.6.3.3 Summary of CS User Plane Changes . 113
5.2.6.4 Impact on PS Control Plane . 113
5.2.6.4.1 PS Control Plane-Before . 113
5.2.6.4.2 PS Control Plane-After . 114
5.2.6.4.3 Summary of PS Control Plane Changes . 115
5.2.6.5 Impact on PS User Plane . 116
5.2.6.5.1 PS User Plane-Before . 116
5.2.6.5.2 PS User Plane-After . 117
5.2.6.5.3 Summary of PS User Plane Changes . 117
6 Evaluation Section . 118
6.1 Enhanced Up . 118
6.2 Combined GANC/SGSN . 122
6.3 GAN Iu Mode . 124
6.4 Comparison of the Proposed Solutions . 126
7 Conclusion . 132
Annex A: Change history . 134
History . 135

ETSI

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3GPP TR 43.902 version 13.0.0 Release 13 6 ETSI TR 143 902 V13.0.0 (2016-01)
Foreword
rd
This Technical Report has been produced by the 3 Generation Partnership Project (3GPP).
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.
Introduction
During the course of Release 6, 3GPP TS 43.318 [2] (Generic access to the A/Gb interface; Stage 2) and
3GPP TS 44.318 [3] (Generic access to the A/Gb interface; Stage 3) were developed that provide access to the 3GPP
core network using generic IP connection. Generic Access Networks, or GAN, is an extension of GSM/GPRS mobile
services into the customer's premises that is achieved by tunnelling certain GSM/GPRS protocols between the
customer's premises and the Core Network over broadband IP network, and relaying them through an unlicensed radio
link inside the customer's premises. GAN is a complement to traditional GSM/GPRS radio coverage, used to enhance
customer premises coverage, increase network capacity and potentially lower costs.
Early deployments of GAN are now ongoing. As part of the continuous process of optimizing their network to better
meet customer demand a number of operators have indicated a need to further enhance the GAN system. Various goals
for such enhancements are documented in section four of the present document. After presentation of the goals, the
present document technical alternatives for how to implement such enhancements to GAN.
ETSI

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3GPP TR 43.902 version 13.0.0 Release 13 7 ETSI TR 143 902 V13.0.0 (2016-01)
1 Scope
The present document contains the results of the feasibility study into the enhancements to Generic Access Networks or
GAN. Considerations include overall re
...