New Security Architecture for IoT. Suku Nair SMU HACNet Labs.

Transcription

1 New Security Architecture for IoT Suku Nair SMU HACNet Labs.

2 Why IoT

3 IoT Systems High coupling of physical and cyber substrates Proliferation of intrinsically small devices Integration at scale

4 Applications of IoT Medical devices and systems Assisted living Traffic control and safety Advanced automotive systems, Process control Energy conservation Environmental control Avionics and aviation software Instrumentation Critical infrastructure (power, water) Distributed robotics (tele-presence) Weapons systems Distributed sensing

5 IoT Structure

6 Security Challenges Key challenges for IoT Ubiquitous data collection Potential for unexpected use of consumer data Heightened security risks Security Secure authentication RFIDs, Smart Cards, Smart Phones Authentic vs. Counterfeit Protection of IP on devices Sensitive information, Embedded software Secure communication CIA Trust anchors and trust extension

7 Traditional Solutions Embed unique key in chip Cryptographic approach Authentication CIA services R [R] k

8 Challenges Key distribution and management Trusted party should embed key EEPROM adds complexity Adversary may physically extract secret key Resource constraints Crypto may not be available AES/SHA-2 needs thousand gates Energy constraints

9 Physical Unclonable Functions Uses inherent variations of manufacturing process Generates unpredictable response, given a stimulus (challenge) Responses are reproducible Challenge PUF Response Tamper-evident & difficult to clone Hard to remove PUF

10 Inter-Chip and Intra-chip Variations Inter-chip For uniqueness, there should be sufficient variation between chips Ideally should be close to 50% Intra-chip Ideally variation should be 0% Variation due to changes in environment Need techniques for reliable reproduction of Challenge-Response

11 One-Time Pad Authentication

12 OCCRA: Overt-Covert Challenge Response Authentication Authentication protocol using embedded sequence of challenge-response numbers Advantages: + Oracle-based authentication + Low-cost, no additional hardware investment on key sharing + Device-centric + Ownership transfer + System scalability + Multi-user provisions + Breach recovery + Volatile-key generation Reader PUF or PUF-like primitives Device

13 OCCRA Protocol Protocol Steps: 1) Setup 2) Authentication 3) Refresh cycle 4) Flush cycle Overt challenge o i Masked by r oi Masked by r oi Response (r oi r cj ) Variable Description (o i,r oi ) Overt challenge-response pair (c j,r cj ) Covert challenge-response pair O C Overt set: consists of a group of overt challenge-response pairs as elements Covert set: consists of a group of covert challenge-response pairs as elements G = (V 1, V 2, E) Bipartite graph G. V 1 and V 2 represent the vertex groups, and E denotes the set of edges that connects between the vertex groups. m ij Mask bits (r oi c j ) P(.) PUF function XOR operation

14 Applications of OCCRA Smart grids Biometrics security

15 Analysis Security Performance Protection against: Replay attacks Cloning/Modeling attacks XOR-leakage attacks Key-values breach Brute-force attack

16 System-Level PUFs Logical/physical PUF comprising multiple PUF elements Protect component-level integrity of systems using fusion of security properties Coupling of components with systems Combination of deterministic parameters with PUF

17 Security Fusion Instead of end-to-end, use global security estimations Suitable or error-prone channels Based on estimations, hence a large number of nodes necessary for accuracy Ideal for nomadic set-up (one time read out) Need not base on an encryption scheme, however, can add encryption to the mix

18 Fusion Architecture

19 Conclusions Security is a key enabler for broad IoT deployment Conventional security models not adequate Security fusion along with device centric security management has potential

20 Questions? Thank you!!!