21-06-2012, 01:52 PM
Security in Near Field CommunicationStrengths and Weaknesses
002 - Security in NFC.ppt (Size: 2.43 MB / Downloads: 45)
What is NFC?
Designed for short distance communication (up to 10 cm)
It’s a contactless card and a contactless reader in one chip
It operates at 13.56 MHz
It’s designed for low bandwidth (max speed is 424 kBaud)
Applications aimed for are
Ticketing
Payment
Device Pairing
Secure Channel is easy
Standard DH Key Agreement
Suffers from Man-in-the-Middle issue
That’s fine with NFC, because right here NFC really provides protection !
Key Agreement – An Alternative
Perfect in theory – Obvious to see
Needs perfect synchronization between Alice and Bob
Amplitude
Phase
Alice and Bob must actively perform this synchronization
Security in practice depends on
Synchronization
Equipment of attacker
Advantages
Cheap (requires no cryptography)
Extremely fast
Conclusion
NFC does not provide any security by itself
Secure Channel is required
Physical properties of NFC protect against Man-in-the-Middle
Establishing a Secure Channel becomes easy