This document discusses security challenges and solutions for machine-to-machine (M2M) communications based on the oneM2M architecture. It identifies three main challenges: the large variety of deployment scenarios, the need to support any device in any deployment, and the inability of devices to make autonomous privacy decisions. The document proposes solutions such as secure communication using TLS/DTLS, remote provisioning of credentials, and access control policies to address these challenges. It also discusses future challenges around decentralization, information sharing between deployments, and more complex authentication and authorization scenarios.

1. © 2014 oneM2M14-Nov-14 1
Facing the Challenges of
M2M Security and Privacy
Phil Hawkes
Principal Engineer at Qualcomm Inc.
phawkes@qti.qualcomm.com
oneM2M www.oneM2M.org

2. © 2014 oneM2M14-Nov-14 2
Overview
• oneM2M Architecture: a quick review
• Challenges
1. Large variety of scenarios
2. Any device in any deployment
3. A device cannot make autonomous “judgment calls”
on privacy
• Solutions
A. Secure communication
B. Remote provisioning
C. Access control policies
• Future Challenges

3. © 2014 oneM2M14-Nov-14 3
oneM2M Architecture:
A Quick Review
• Entities
– Nodes (=Devices)
– Common Service Entity
(CSE)
– Application Entity (AE)
• Interactions:
– Mca: AE-to-CSE
– Mcc, Mcc’: CSE-to-CSE
– RESTful
• For more info see
webinar Taking a look
inside oneM2M
CSE
CSE CSE
CSE CSE
AE
AE
AE
AE
AE
AE
AE
CSE
Field Domain
Infrastructure
Domain

4. © 2014 oneM2M14-Nov-14 4
Challenges
1. Large variety of scenarios
2. Any device in any deployment
3. A device cannot make autonomous
“judgment calls” on privacy

5. © 2014 oneM2M14-Nov-14 5
Challenges
1. Large variety of deployments
– “Assets” that need protecting can be unique to a
deployment
• Content confidentiality, content integrity, anonymity, traffic
efficiency
– Environment can be unique to a deployment
• Does wired or wireless transport layer provide adequate
security?
• Tamper-resistance considerations
– (Continued on next slide)
2. Any device in any deployment
3. A device cannot make autonomous “judgment
calls” on privacy

6. © 2014 oneM2M14-Nov-14 6
Challenges
1. Large variety of deployments (continued)
– Variety of authentication scenarios
• Pre-shared Key provisioned to both by end-points
• PKI/Certificates (asymmetric cryptography)
• Centralized authentication
2. Any device in any deployment
3. A device cannot make autonomous
“judgment calls” on privacy

7. © 2014 oneM2M14-Nov-14 7
Challenges
1. Large variety of deployment scenarios
2. Any device in any deployment
– Interoperability: agree on minimal set of cipher suites
– Credential management
a. Provisioning at manufacture
b. Human-assisted provisioning during deployment
– e.g. manual entry, via USB
c. Remote provisioning of fielded devices
d. Derivation from pre-existing credentials (e.g. transport
network)
Note: a, b are enabled but not specified by oneM2M
3. A device cannot make autonomous “judgment
calls” on privacy

8. © 2014 oneM2M14-Nov-14 8
Challenges
1. Large variety of scenarios
2. Any device in any deployment
3. A device cannot make autonomous “judgment
calls” on privacy
– M2M/IoT may expose information about our lives
without our awareness
– Privacy = who can access information about me
– CSE needs to determine: “Should I allow access?”
– Can’t ask human to make case-by-case judgment call
– CSE needs clear rules

9. © 2014 oneM2M14-Nov-14 9
Challenges & Solutions
1. Large variety of
scenarios
2. Any device in any
deployment
3. A device cannot make
“judgment calls” on
privacy
A. Secure communication
various authentication options
B. Remote provisioning
various authentication options
C. Access Control Policies
expresses wide variety of rules

10. © 2014 oneM2M14-Nov-14 10
Secure Communication:
Example
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
E-Health
Web-application

11. © 2014 oneM2M14-Nov-14 11
Secure Communication:
Example
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
1. AE1 passes sensor
reading to CSE1
CoAP
UDP

12. © 2014 oneM2M14-Nov-14 12
Secure Communication:
Example
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
1. AE1 passes sensor
reading to CSE1
2. CSE1 forwards
sensor reading to
CSE2
HTTP
TCP
CoAP
UDP

13. © 2014 oneM2M14-Nov-14 13
Secure Communication:
Example
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
1. AE1 passes sensor
reading to CSE1
2. CSE1 forwards
sensor reading to
CSE2
3. AE2 retrieves
sensor reading
from CSE2
CoAP
UDP
HTTP
TCP
HTTP
TCP

14. © 2014 oneM2M14-Nov-14 14
Secure Communication
• Hop-by-Hop
– Transited CSEs see
clear text
– Trusted to behave
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server

15. © 2014 oneM2M14-Nov-14 15
Secure Communication
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
CoAP
DTLS
UDP
• Hop-by-Hop
• TLS/DTLS v1.2
– DTLS if UDP transport

16. © 2014 oneM2M14-Nov-14 16
Secure Communication
• Hop-by-Hop
• TLS/DTLS v1.2
– DTLS if UDP transport
– TLS if TCP transport
– Sometimes write
(D)TLS or just TLS for
both CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
HTTP
TLS
TCP
HTTP
TLS
TCP

17. © 2014 oneM2M14-Nov-14 17
Secure Communication
• Hop-by-Hop
• TLS/DTLS v1.2
• AE-CSE
– AE: TLS Client (C)
– CSE: TLS Server (S)
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
C S
C S

18. © 2014 oneM2M14-Nov-14 18
Secure Communication
• Hop-by-Hop
• TLS/DTLS v1.2
• AE-CSE
– AE: TLS Client (C)
– CSE: TLS Server (S)
• CSE-CSE
– CSE1: TLS Client (C)
– CSE2: TLS Server (S)
CSE2
CSE1
AE2
AE1
Infrastructure
Domain
Field Domain
Sensor Gateway
M2M SP’s Server
Web App
Server
C S
C
C S
S

19. © 2014 oneM2M14-Nov-14 19
Authentication Options
• Pre-Shared Key (PSK)
– TLS Client & Server provisioned with a shared key#
• Certificate
– TLS Client & Server both have certificates
• M2M Authentication Function (MAF)
– MAF operated by 3rd Party or M2M Service Provider
– TLS Client and MAF provisioned with a shared key#
– MAF assists authentication of TLS Client & Server
#This shared key can be remotely provisioned

20. © 2014 oneM2M14-Nov-14 20
Certificates
• Somewhat aligned with CoAP Security RFC7252
• X.509/PKIX (RFC 5280)
• RawPublicKey Certificates
– Contains only X.509 SubjectPublicKeyInfo element
– Suits less complex deployments & debugging
• Certificates chaining to a trust anchor. E.g.
– Device Certificate (e.g. manufacturer issued)
– M2M SP issued certificate identifying CSE or AE

21. © 2014 oneM2M14-Nov-14 21
Remote Provisioning
• Process provisioning a shared key to two entities
• M2M Enrolment Function (MEF)
– Assists remote provisioning
– Operated by 3rd Party or M2M Service Provider
• Mechanisms for establishing shared key
– TLS Client & MEF perform (D)TLS, export shared key
• PSK
• Certificates
– Derived from Network Access credentials
• Network Access Provider assists in mutual authentication
• Generic Bootstrapping Architecture (GBA) 3GPP TS 33.220

22. © 2014 oneM2M14-Nov-14 22
Access Control Requirements
• oneM2M uses a RESTful architecture
– API: request to perform an operation on a resource
– Operations: Create, Retrieve, Update, Delete
– Webinar Taking a look inside oneM2M has more info
• CSEs can’t make resource access judgement calls
• CSE need clear rules dictating, for each resource
– WHO (which CSEs and AEs) are authorized to access,
– WHAT operations (see above), and under…
– WHICH circumstances (e.g. time, location of entity)

23. © 2014 oneM2M14-Nov-14 23
Access Control Policies (ACP)
Resources
Resource1
Resource4
Resource3
Resource2
ACP1
ACP3
ACP2
ACP Rule1
ACP Rule2
links contains
ACP Rule3
Resource access is authorized upon satisfying at least one ACP
rule in one of the linked ACPs

24. © 2014 oneM2M14-Nov-14 24
Resource1
Resource4
Resource3
Resource2
ACP1
ACP3
ACP2
ACP Rule1
ACP Rule2
links contains
WHO: entities
CSE-ID
AE-ID
WHICH: circumstances
Time,
location,
IP address
WHAT: operations
Create,
Retrieve
Update
Delete
with conditions on
ACP Rule3
ACP rule is satisfied if WHO and WHAT and WHICH are satisfied
by requesting entity, requested operation and circumstances
Access Control Policies (ACP)
Resources

25. © 2014 oneM2M14-Nov-14 25
oneM2M Security Documents
• TR-0008 “Analysis of Security Solutions for the
oneM2M System”
http://onem2m.org/images/files/deliverables/oneM2M_TR-0008-Security-V1_0_0.doc
• TS-0003 “Security Solutions”
http://onem2m.org/images/files/deliverables/TS-0003-Security_Solutions-V-2014-08.pdf
• Latest versions available from
ftp://ftp.onem2m.org/Work%20Programme/WI0007/

26. © 2014 oneM2M14-Nov-14 26
Limitations of initial release
• A “minimum deployable solution” addressing
short term needs
• Focus: Vertically deployed industrial applications
– Centralized client-server architectures
– Most devices have limited number of static
connections
– Deployments are managed by skilled workforce
– Nodes are trusted to behave
• Our solutions meet these needs while having a
place in future M2M/IoT (consumer) scenarios

27. © 2014 oneM2M14-Nov-14 27
Future Challenges
• Decentralization
– Increasingly complex interactions
• Sharing Information between deployments
• Complex authentication and authorization scenarios
• Confidentiality & integrity concerns
– Unskilled Consumers managing their “Things”
• Technological Challenges:
– End-to-End (multi-hop) message security
– Many connections per device
– Authentication & Authorization mechanisms

28. © 2014 oneM2M14-Nov-14 28
Conclusion:
Challenges & Solutions
1. Large variety of
scenarios
2. Any device in any
deployment
3. A device cannot make
“judgment calls” on
privacy
A. Secure communication
various authentication options
B. Remote provisioning
various authentication options
C. Access Control Policies
expresses wide variety of rules

29. © 2014 oneM2M14-Nov-14 29
Join us for the next webinar
27 November 2014 at 0700 UTC
“On Management, Abstraction &
Semantics”
by Dr. Yongjing Zhang
Standard Research Project Lead
at Huawei Technologies Co., Ltd
http://www.onem2m.org/btchannel.cfm

30. © 2014 oneM2M14-Nov-14 30
Check out the recorded webinars
“How standardization enables the next
internet evolution”
by Marc Jadoul
Strategic Marketing Director, Alcatel-Lucent
http://www.onem2m.org/btchannel.cfm
“Taking a look inside”
by Nicolas Damour
Senior Manager for Business and Innovation Development,
Sierra Wireless

31. © 2014 oneM2M14-Nov-14 31
Join us at the
oneM2M showcase event
9 December 2014, Sophia-Antipolis, France
(free of charge, but online registration is required)
• OneM2M project partners, rationale and goals
• OneM2M Service Layer Specification release
• Showcase demos that demonstrate oneM2M “live"
http://www.onem2m.org/Showcase
Followed by the ETSI M2M workshop

32. © 2014 oneM2M14-Nov-14 32
Q & A

33. © 2014 oneM2M14-Nov-14 33
Backup Slides

34. © 2014 oneM2M14-Nov-14 34
PSK-Based Authentication
Client Server

35. © 2014 oneM2M14-Nov-14 35
PSK
Client Server
1. Provision identical PSK, PSK-ID to A, B
PSK, PSK-ID PSK, PSK-ID

36. © 2014 oneM2M14-Nov-14 36
PSK
2. TLS/DTLS
A provides PSK-ID
B identifies PSK from PSK-ID
Client Server
PSK, PSK-ID PSK, PSK-ID

37. © 2014 oneM2M14-Nov-14 37
PSK
2. (D)TLS
A provides PSK-ID
B identifies PSK from PSK-ID
• Advantages:
– Simple Concept
• Challenges:
– May need multiple
keys provisioned
– Doesn’t scale well
Client Server
PSK, PSK-ID PSK, PSK-ID

38. © 2014 oneM2M14-Nov-14 38
PKI/Certificate-Based
Authentication
Client Server

39. © 2014 oneM2M14-Nov-14 39
PKI
Client Server
Client’s Cert Server’s Cert
1. Provision certificate 1’. Provision certificate

40. © 2014 oneM2M14-Nov-14 40
PKI
Client Server
2. Configure trust anchors 2’. Configure trust anchors
Client’s Cert Server’s Cert
Client’s
Trust Anchors
Server’s
Trust Anchors

41. © 2014 oneM2M14-Nov-14 41
PKI
Client Server
Client’s Cert Server’s Cert
Client’s
Trust Anchors
Server’s
Trust Anchors2. (D)TLS
Validate client cert
against
server’s trust anchors
Validate server’s cert
against
client’s trust anchors

42. © 2014 oneM2M14-Nov-14 42
MAF Assisted
(D)TLS
Client
MAF
(D)TLS
Server

43. © 2014 oneM2M14-Nov-14 43
MAF Assisted
(D)TLS
Client
1. Provision symmetric key Km, KmId
MAF
(D)TLS
Server
Km, KmID Km, KmId

44. © 2014 oneM2M14-Nov-14 44
MAF Assisted
(D)TLS
Client
2. Generate Kc, KcId from Km
MAF
(D)TLS
Server
Km, KmID Km, KmId
Kc, KcId Kc, KcId

45. © 2014 oneM2M14-Nov-14 45
MAF Assisted
(D)TLS
Client
MAF
(D)TLS
Server
3a. (D)TLS: KcId
Kc, KcId Kc, KcId

46. © 2014 oneM2M14-Nov-14 46
MAF Assisted
(D)TLS
Client
MAF
(D)TLS
Server
3a. (D)TLS: KcId 3b. KcId
Kc, KcId Kc, KcId

47. © 2014 oneM2M14-Nov-14 47
MAF Assisted
(D)TLS
Client
MAF
(D)TLS
Server
3a. (D)TLS: KcId 3b. KcId
3c. Kc
Kc, KcIdKc, KcIdKc, KcId

48. © 2014 oneM2M14-Nov-14 48
MAF Assisted
(D)TLS
Client
MAF
(D)TLS
Server
3a. (D)TLS: KcId 3b. KcId
(D)TLS w/ Kc 3b. Kc
Kc, KcIdKc, KcIdKc, KcId

49. © 2014 oneM2M14-Nov-14 49
Remote Provisioning PArticipants
• Process provisions a shared key to two entities
• M2M Enrolment Function (MEF)
– Assists remote provisioning
– Operated by 3rd Party or M2M Service Provider
• Enrolee
– Entity requesting to be provisioned
• Enrolment Target
– Other entity that will ends up with the shared key

50. © 2014 oneM2M14-Nov-14 50
Remote Provisioning
M2M Enrolment
FunctionEnrolee
Enrolment
Target

51. © 2014 oneM2M14-Nov-14 51
Remote Provisioning
Mutual Authentication
M2M Enrolment
FunctionEnrolee
Enrolment
Target

52. © 2014 oneM2M14-Nov-14 52
Remote Provisioning
Mutual Authentication
M2M Enrolment
FunctionEnrolee
Enrolment
Target
Generate Ke, KeId Generate Ke, KeId
Ke, KeId
Ke, KeId

53. © 2014 oneM2M14-Nov-14 53
Remote Provisioning
M2M Enrolment
FunctionEnrolee
Enrolment
Target
Ke, KeId
Ke, KeId

54. © 2014 oneM2M14-Nov-14 54
Remote Provisioning
M2M Enrolment
FunctionEnrolee
Enrolment
Target
Ke, KeId
Ke, KeId
KeId

55. © 2014 oneM2M14-Nov-14 55
Remote Provisioning
M2M Enrolment
FunctionEnrolee
Enrolment
Target
Ke, KeId
Ke, KeId
KeId
+ Enrolment
Target ID
+ Enrolment
Target ID
Shared Key
Shared Key

56. © 2014 oneM2M14-Nov-14 56
Remote Provisioning
M2M Enrolment
FunctionEnrolee
Enrolment
Target
KeId
Shared Key
Shared Key
Shared Key

57. © 2014 oneM2M14-Nov-14 57
Remote Provisioning
M2M Enrolment
FunctionEnrolee
Enrolment
Target
Shared Key
Shared Key

58. © 2014 oneM2M14-Nov-14 58
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
Network Access
Credentials
GBA Bootstrap Server
Function
(plays role of MEF)
Network Access
Credentials

59. © 2014 oneM2M14-Nov-14 59
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
Network Access
Credentials
GBA Bootstrap Server
Function
(plays role of MEF)
Network Access
Credentials

60. © 2014 oneM2M14-Nov-14 60
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
Network Access
Credentials
Network Access
Credentials
GBA Bootstrap Server
Function
(plays role of MEF)
B-TID,
Ks
B-TID,
Ks

61. © 2014 oneM2M14-Nov-14 61
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
GBA Bootstrap Server
Function
(plays role of MEF)
B-TID,
Ks
(D)TLS: B-TID
B-TID,
Ks

62. © 2014 oneM2M14-Nov-14 62
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
GBA Bootstrap Server
Function
(plays role of MEF)
B-TID,
Ks
B-TID(D)TLS: B-TID
B-TID,
Ks

63. © 2014 oneM2M14-Nov-14 63
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
GBA Bootstrap Server
Function
(plays role of MEF)
B-TID,
Ks
Shared
Key
(D)TLS: B-TID B-TID
TLS Server FQDN
B-TID,
Ks
Shared
Key

64. © 2014 oneM2M14-Nov-14 64
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
GBA Bootstrap Server
Function
(plays role of MEF)
Shared
Key
Shared Key
Shared
Key
(D)TLS: B-TID B-TID
Shared
Key

65. © 2014 oneM2M14-Nov-14 65
GBA
UE
(hosts
TLS
Client)
Network Access
Authentication Server
(HSS, HLR, AAA)
TLS
Server
GBA Bootstrap Server
Function
(plays role of MEF)
Shared
Key
Shared
Key
Continue
(D)TLS
(D)TLS: B-TID