NFC modes and security

1. NFC Operating Modes and
Security
By Rajeev Verma and Alessandro Sarra

2. Overview
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Brief Introduction
Induction coupling
Modes
Essentials of each mode
Security
Future Development
Conclusions
References

3. Introduction to NFC
● Communication technology which works on physical
touch (4-10cm) of the devices.
● Benefits:
Intuitive
Versatile
Open and standard based
Inherently secure
Interoperable
Security-ready

4. Induction Coupling
Induction coupling is the technology behind the data
transfer in NFC communication.
Power received by receiver:
C is coupling coefficient which decides the effectiveness
in communication.

5. NFC Operating Modes

6. NFC Modes : Card Emulation Mode
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Emulate contact-less smart card
Communicate with RFID readers
Mobile payment and ticketing
Compatible to existing infrastructure

7. Card Emulation Mode Communication
Architecture

8. NFC Operating Modes

9. NFC Modes :Reader/Writer Mode
● Communicate with:
○ Smart Cards
○ NFC tags
● Embedded in readable object
● Sends Information Passively

10. Communication Architecture of Reader/Writer Mode

11. NDEF: NFC Data Exchange Format
● Standardized format
○ Store data on tags
○ Transport data
● Lightweight Binary
○ Encapsulation
■ Single message
construct
■ One or more payload

12. NDEF Message

13. NDEF : Record
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MB - msg begin
ME - msg end
CF - Chunk Flag
○ CF = 0 No chunk.
SR - Short Record
○ SR=0 : Single octet msg.
○ Max 255 octets
IL - Identification length
○ IL = 0 : ID Length omitted from
Record.
Type Length : Define length of Type
field octet
Payload Length

14. NDEF : TNF
● → structure of type
field
● → 3 bits field
● Type field finally have
the type for message.

15. NFC Operating Modes

16. NFC Modes : Peer-to-Peer
● 2 Devices
● Direct Communication
● Share Bluetooth or WiFi
setup
● Send photos or small text

17. NFC Modes: Peer-to-Peer
● Communication Architecture

18. Peer-to-Peer mode essentials
● Protocol Stack
● LLCP Protocol Services
○ Connectionless transport
○ Connection oriented transport
○ Link related Services
○ Asynchronous Balanced communication
○ Protocol Multiplexing
OSI vs LLCP

19. Security Aspects in NFC
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Eavesdropping
Data Corruption
Data Modification
Relay Attack
Lost Property
Walk-off
NDEF and Signature Recognition
Weaknesses of Digital Signing

20. Eavesdropping
● Even though Range is small in NFC, still signals are
retrievable from 1mt to 10mt.
● Using a secure channel can be a solution for NFC data
transfer.

21. Data Corruption
● Attacker can attempt to disrupt communications by
forcefully sending seemingly valid data.
● Channel can be blocked for ongoing data transmission
between devices.
Solution:
● Device can report the higher power used for
communication which is possibly the corrupted Data.

22. Data Modification
● Data can be maliciously altered in the communication
path keeping the data format same.
Solution:
● 100% modulation and Miller encoding can prevent Data
Modification.
● Data transfer at 106 baud rate is least susceptible for
modification but eavesdropping probability can be
increased.

23. Man in the middle
● Communication between two parties can is interrupted
by third.
● Potentially possible when two mobile devices are
actively communicating in peer-to-peer mode.
● Communication in other modes are immune to this
attack.

24. Walk-off
● Attacks are possible during access to a secure NFC
function or data is given prior to it timing out after a
period of inactivity.
Solution:
● Wireless authentication factor known as an electronic
"leash"
● Devices are leashed till the device goes out of the
range.

25. Relay Attack
● Similar to Man in Middle attack, adversary has to
forward the request of the reader to the victim.
● Attacker potentially has access any service directly
related to the data being sent.

26. Lost Property
● If the NFC device is lost, it will open access to anyone
who finds it and can pass authenticity checks.
● Extended security concepts do exist at the application
level that provide theft protection and tracking.

27. NDEF and Signature Recognition
● Digital Signature Records can provide encryption
through use of public-key cryptography.
● Digital Signature Records, when coupled with the NFC
Data Exchange Format, can serve as a feasible means
of security.
Benefits:
Authentic
→ There is a unique signer.
Unforgettable → Only the signature owner may
create a key.
Non-reusable: → The signature is bound the signed

28. Weakness
● Digital Signing is still a weakness for NFC
communication.
● Digital signing can resolve the problem of device
authentication and reliable event triggering.

29. Future Applications
● Interactive data
● NFC Tag Everything!!!
○ Tag doubles as bar-code
● Mobile Device Transactions
● Organization and Awareness

30. Future Development
● Wireless charging
○ reception
○ transmission
○ both
● Dock for
home/office/car
● 13.56MHz
● 1 Watt Max
● Energy Saving

31. Future Development
● SD Card Integration
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Isolated Antenna
Memory Controller
Card Controller
Memory
● OTA, MiFare, JCOP,
Perso

32. Conclusion
● Emerging Technology
● Pros
○ Power-saving
○ Low Profile
● Cons
○ Inefficient
○ Hard to ‘Sell’

33. Questions??

34. Thank You!
[1] V. Coskun, K. Ok, et al., “NFC Operating Modes,” Near Field Communication: From Theory to Practice, Chichester, United Kingdom: John
Wiley and Sons Ltd., 2012, ch. 4.
[2] S. A. Ahson and I. Mohammad, “Security in NFC,” in Near Field Communications Handbook, Boca Raton: CRC Press, 2012, ch. 2, sec. 2,
pp. 26-45
[3] NFC Record Type Definition, NFC Forum Technical Specification, Rev. 1.0, Jul. 2006.
[4] E. Strommer, M. Jurvansuu, T. Tuikka, A. Yisaukko-oja, H. Rapakko, and J. Vesterinen, “NFC-enabled wireless charging,” in Near Field
Communication (NFC), 2012 4th International Workshop on, march 2012, pp. 36-41.
[5] M. Roland and J. Langer, “Digital Signature Records for the NFC Data Exchange Format,” in Proceedings of the Second International
Workshop on Near Field Communication (NFC 2010), Monaco, Apr. 2010, pp. 71-76.
[6] G. Madlmayr, J. Langer, C. Kanter, and J. Scharinger, “NFC Devices: Security and Privacy,” in Third International Conference on Availability,
Reliability and Security, March 2008, pp.642-647.
[7] Yen-Sheng Chen, “Analysis of antenna coupling in near-field RFID systems,” in IEEE AP-S Int. Symp. Dig., Jun. 2009, pp. 1-4.
[8] P. Dobrigkeit, T. Flach, P. Faymonville, J. Muller. Exchange of contact data between mobile phones using NFCIP” in Proceedings of 4th
European Workshop on RFID Systems and Technologies (RFID SysTech), 2008, pp. 1-9.
[9] S. Wu, “Promoting Collaborative Mobile Payment by Using NFC-Micro SD Technology,” in Tenth International Conference on Services
Computing, Jun. 2013, pp. 454-461.