ETSI TR 133 937 V14.0.0 (2017-04)

Universal Mobile Telecommunications System (UMTS); LTE; Study of mechanisms for Protection against Unsolicited Communication for IMS (PUCI) (3GPP TR 33.937 version 14.0.0 Release 14)

RTR/TSGS-0333937ve00

General Information

• Status: Published
• Publication Date: 10-Apr-2017
• Technical Committee: 3GPP SA 3 - Security
• Current Stage: 12 - Completion
• Completion Date: 11-Apr-2017

Standards Content (Sample)

ETSI TR 133 937 V14.0.0 (2017-04)






TECHNICAL REPORT
Universal Mobile Telecommunications System (UMTS);
LTE;
Study of mechanisms for Protection against
Unsolicited Communication for IMS (PUCI)
(3GPP TR 33.937 version 14.0.0 Release 14)

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3GPP TR 33.937 version 14.0.0 Release 14 1 ETSI TR 133 937 V14.0.0 (2017-04)



Reference
RTR/TSGS-0333937ve00
Keywords
LTE,SECURITY,UMTS
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3GPP TR 33.937 version 14.0.0 Release 14 2 ETSI TR 133 937 V14.0.0 (2017-04)
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 "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 33.937 version 14.0.0 Release 14 3 ETSI TR 133 937 V14.0.0 (2017-04)
Contents
Intellectual Property Rights . 2
Foreword . 2
Modal verbs terminology . 2
Foreword . 7
1 Scope . 8
2 References . 8
3 Definitions, Symbols and Abbreviations . 9
3.1 Definitions . 9
3.2 Symbols . 9
3.3 Abbreviations . 9
4 System Environment for PUCI . 11
4.1 Architectural Issues . 11
4.1.1 Introduction. 11
4.1.2 Originating/Terminating UC Identification and Scoring . 12
4.1.3 Central/Distributed UC Identification and Scoring . 13
4.1.3.1 Distributed UC Identification and Distributed UC Scoring . 13
4.1.3.2 Distributed UC Identification and Central UC Scoring. 15
4.1.4 Standardized/Vendor-Specific UC Scoring Algorithms . 16
4.2 Non-Technical Conditions. 17
4.2.1 Prevention of Unsolicited Communication in an Operator Controlled Environment . 17
4.2.1.1 Introduction . 17
4.2.1.2 Current SPIT/UC Prevention Measures . 17
4.3 Technical versus Legal Issues . 19
4.3.1 Introduction. 19
4.3.2 UC Legislation . 19
4.3.2.1 Definition of UC . 19
4.3.2.2 Definition of UC Communication Services . 20
4.3.2.3 Consent Achievement about UC Communication . 21
4.3.3 Liability . 21
4.3.4 Privacy . 22
4.3.5 Conclusion . 23
4.4 Coexistence with Single Radio-VCC, ICS, and SC . 23
5. PUCI Risk Analysis . 25
5.1 General . 25
5.2 UC Threats & Scenarios . 25
5.2.2 General Scenario . 25
5.2.3 Privacy Violation . 26
5.2.3.1 Privacy Violation Scenarios . 26
5.2.3.1.1 Bulk UC (Advertising) . 26
5.2.3.1.2 Targeted UC (Stalker) . 26
5.2.3.2 Privacy Violation Risks . 27
5.2.4 Contentious Incoming Call Service Charge . 27
5.2.4.1 Contentious Incoming Call Service Charge Scenarios . 28
5.2.4.1.1 UC While Call Forwarding is Enabled . 28
5.2.4.2 Contentious Incoming Call Service Charge Risks . 28
5.2.5 Contentious Roaming Cost . 28
5.2.5.1 Contentious Roaming Cost Scenarios . 28
5.2.5.1.1 UC While Roaming . 28
5.2.5.2 Contentious Roaming Cost Risks . 28
5.2.6 Non-disclosure of Call Back Cost . 28
5.2.6.1 Non-disclosure of Call Back Cost Scenarios . 28
5.2.6.1.1 Baiting for Premium Number Call Back . 28
5.2.6.2 Non-disclosure of Call Back Cost Risks . 29
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3GPP TR 33.937 version 14.0.0 Release 14 4 ETSI TR 133 937 V14.0.0 (2017-04)
5.2.7 Phishing . 29
5.2.7.1 Phishing Scenarios . 29
5.2.7.1.1 Messaging/Voice Phishing for Bank Account Information . 29
5.2.7.1.2 Voice Phishing for Identity Theft . 29
5.2.7.2 Phishing Risks . 29
5.2.8 Network Equipment Hijacking . 29
5.2.8.1 Network Equipment Hijacking Scenarios . 29
5.2.8.1.1 Compromised IMS Network Element . 29
5.2.8.2 Network Equipment Hijacking Risks . 29
5.2.9 User Equipment Hijacking . 30
5.2.9.1 User Equipment Hijacking Scenarios . 30
5.2.9.1.1 Botnets Using User Equipment . 30
5.2.9.1.2 Malware Distribution Through Bulk UC . 30
5.2.9.2 User Equipment Hijacking Risks . 30
5.2.10 Mobile Phone Virus . 30
5.2.10.1 Mobile Phone Virus Scenarios . 30
5.2.10.1.1 Exposure of User Privacy . 30
5.2.10.1.2 Destroying Mobile Phone Software and Hardware . 30
5.2.10.1.3 Distributing Illegal Information and Virus . 30
5.2.10.1.4 Junk Data Distribution through Bulk UC Resulting in User Additional Charges & Network
Traffic Jam . 31
5.2.10.2 Mobile Phone Virus Risks . 31
5.2.11 Sender Impersonation UC . 31
5.2.11.1 Sender Impersonation UC Scenarios . 31
5.2.11.1.1 Forged Sender UC Received through Interworking with VoIP Operator . 31
5.2.11.2 Sender Impersonation UC Risks . 31
5.2.12 Unavailability of Service or Degraded Service Quality . 31
5.2.12.1 Unavailability of Service or Degraded Service Quality Scenarios . 31
5.2.12.1.1 UC flood leads to Degraded Service Quality . 31
5.2.12.2 Unavailability of Service or Degraded Service Quality Risks . 31
5.2.13 Negative Service Preconception Leading to Non-adoption . 32
5.3 Specific UC threats in non-IMS inter-connections . 32
5.3.1 Introduction. 32
5.3.2 Legal assumptions . 32
5.3.3 Network assumptions . 33
5.3.4 Security assumptions . 34
5.3.5 High risk specific threats . 34
6 Security Requirements . 36
6.1 Void . 36
6.2 3GPP Security Requirements . 36
7 Supporting Mechanisms and Solution Alternatives . 37
7.1 Review of Measures and Potential Supporting Mechanisms . 37
7.1.1 Measure for Protection Against Privacy Violation . 37
7.1.1.1 Measures Against Bulk UC . 37
7.1.1.2 Measures Against Targeted UC . 40
7.1.2 Measures for Protection Against Contentious Incoming Call Service Charge . 40
7.1.3 Measures for Protection Against Contentious Roaming Cost . 40
7.1.4 Measures for Protection Against Non-disclosure of Call Back Cost . 40
7.1.5 Measures for Protection Against Phishing . 41
7.1.6 Measures for Protection Against Network Equipment Hijacking . 41
7.1.7 Measures for Protection Against User Equipment Hijacking . 41
7.1.8 Measures for Protection Against Mobile Phone Virus . 42
7.1.9 Measures for Protection Against Sender Impersonation UC . 43
7.1.10 Measures for Protection Against Unavailability of Service or Degraded Service Quality . 43
7.2 IMR-Based Solution Approach . 43
7.2.1 General . 43
7.2.2 IMR Approach . 44
7.2.3 From Requirements to Solution . 45
7.2.4 IMR Solution Variations . 48
7.2.4.1 General . 48
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3GPP TR 33.937 version 14.0.0 Release 14 5 ETSI TR 133 937 V14.0.0 (2017-04)
7.2.4.2 IMR Solution Based on Supplementary Services . 49
7.2.5 Detailed Solution . 50
7.2.5.1 Overview . 50
7.2.5.2 Simple PUCI Invocation . 50
rd
7.2.5.3 PUCI with Supplementary Services and 3 Party PUCI AS . 52
7.2.5.4 Standardization . 54
7.3 SPIT/UC Protection with Supplementary Services . 54
7.3.1 Introduction. 54
7.3.2 Supplementary Services usable for SPIT/UC Prevention . 55
7.3.3 SPIT/UC Prevention Scenarios with Supplementary Services . 56
7.3.3.1 Simple Black List combined with Anonymous Call Rejection . 56
7.3.3.2 White List with Consent Mailbox . 57
7.3.3.3 White List with Consent Mailbox, protected by a Black List . 57
7.3.3.4 Sophisticated SPIT/UC Prevention Profile with Audio CAPTCHA . 58
7.3.3.5 White List Consent Achievement by IN Server . 59
7.3.3.6 SPIT/UC Feedback by User Based on Key Pad Entries in the Phone . 61
7.4 Contextual Information . 61
7.4.1 Introduction. 61
7.4.2 IMS Mechanism Outline . 62
7.4.3 Use of Contextual Information . 62
7.4.3.1 General . 62
7.4.3.2 Reaction . 63
7.4.3.3 Marking . 63
7.4.3.4 Sharing of Information . 63
7.4.3.5 Impact on Supplementary Services . 64
7.5 UC protection framework for non-IMS interconnection: the Open Proxy Handshake . 64
7.5.1 Objectives . 64
7.5.2 Assumptions . 65
7.5.3 Basic principles . 66
7.5.4 Detailed principles . 67
7.5.4.1 No shared secret between domain A and domain B . 68
7.5.4.2 A shared secret is established between domain A and domain B. 69
7.6 Alternative Methods for Authentication of Originating Network . 70
7.6.1 Introduction. 70
7.6.2  P-Asserted-Identity . 71
7.6.3 SIP Identity . 71
7.6.4  Trusted Interconnect with IPSec . 72
7.6.5 Trusted Interconnect with IPSec combined with P-Asserted-Identity . 72
7.6.6 Summary . 73
8 Evaluation of Solution Alternatives . 74
8.1 Evaluation Criteria . 74
8.2 Evaluation of Alternatives . 77
8.3 Usage Space . 85
9 Potential PUCI Architecture . 87
9.1 High-level architecture, mapping PUCI functionality to the IMS architecture . 87
9.2 Centralized/Distributed PUCI AS . 87
9.3 UC identification / UC prevention . 88
9.4 Originating/Terminating UC identification and prevention . 88
9.5 Real-time / non-real-time UC identification and prevention . 89
9.6 Standardized versus Vendor specific aspects . 89
9.7 Interaction with non-IMS networks . 90
10 Summary . 91
Annex A (informative): Usability and Business Aspects . 92
A.1 Usability Consideration . 92
A.1.1 User Prompting . 92
A.1.2 User vs UE . 92
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3GPP TR 33.937 version 14.0.0 Release 14 6 ETSI TR 133 937 V14.0.0 (2017-04)
Annex B (informative): Analysis of UC protection mechanisms for non-IMS
interconnection . 93
B.1 Solutions based on sender identity . 93
B.2 Call analysis and UC identification . 93
B.3 Network solutions . 94
B.4 Applicative solutions . 94
Annex C (informative): Change history .
...