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PUFs at a Ulrich Rhrmair Technische Universitt Mnchen Glance - - PowerPoint PPT Presentation

Design Automation and Test in Europe 2014 PUFs at a Ulrich Rhrmair Technische Universitt Mnchen Glance Daniel E. Holcomb University of Michigan This work was supported in part by C-FAR, one of six centers of STARnet, a


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SLIDE 1

Design Automation and Test in Europe 2014

PUFs at a Glance

Ulrich Rührmair Technische Universität München

  • Daniel E. Holcomb

University of Michigan

This work was supported in part by C-FAR, one of six centers of STARnet, a Semiconductor Research Corporation program sponsored by MARCO and DARPA, and NSF CNS-0845874.

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SLIDE 2

PUFs at a Glance DATE 2014

ABSTRACT

We introduce the notion of a Physical Random Function (PUF). We argue that a complex integrated circuit can be viewed as a silicon PUF and describe a technique to identify and authenticate individual integrated circuits (ICs). We describe several possible circuit realizations of differ-

Silicon Physical Random Functions∗

Blaise Gassend, Dwaine Clarke, Marten van Dijk† and Srinivas Devadas

Massachusetts Institute of Technology Laboratory for Computer Science Cambridge, MA 02139, USA

gassend,declarke,marten,devadas @mit.edu

Physical Unclonable Functions

2

Research Mentions by Year Year

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SLIDE 3

PUFs at a Glance DATE 2014

Overview

  • 1. Brief introduction to PUFs
  • 2. Weak PUFs and applications
  • 3. Strong PUFs and applications
  • 4. Conclusions

3

Context and motivation for remainder of session

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SLIDE 4

PUFs at a Glance DATE 2014

f

Physical Unclonable Functions

4

Challenges Responses

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SLIDE 5

PUFs at a Glance DATE 2014

f

Physical Unclonable Functions

❖ Function ❖ Map challenges to responses

4

Challenges Responses

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SLIDE 6

PUFs at a Glance DATE 2014

f

Physical Unclonable Functions

❖ Function ❖ Map challenges to responses ❖ Physical ❖ Mapping depends on physical variations

4

Challenges Responses

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SLIDE 7

PUFs at a Glance DATE 2014

f

Physical Unclonable Functions

❖ Function ❖ Map challenges to responses ❖ Physical ❖ Mapping depends on physical variations

4

Challenges Responses

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SLIDE 8

PUFs at a Glance DATE 2014

f

Physical Unclonable Functions

❖ Function ❖ Map challenges to responses ❖ Physical ❖ Mapping depends on physical variations

4

PUF Characterized by Challenge-Response Pairs (CRPs) Challenges Responses

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SLIDE 9

PUFs at a Glance DATE 2014

f

Physical Unclonable Functions

❖ Function ❖ Map challenges to responses ❖ Physical ❖ Mapping depends on physical variations ❖ Unclonable ❖ No compact model exists, and CRP space is too large

for dictionary

4

PUF Characterized by Challenge-Response Pairs (CRPs) Challenges Responses

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SLIDE 10

PUFs at a Glance DATE 2014

f

Physical Unclonable Functions

❖ Function ❖ Map challenges to responses ❖ Physical ❖ Mapping depends on physical variations ❖ Unclonable ❖ No compact model exists, and CRP space is too large

for dictionary

4

PUF Characterized by Challenge-Response Pairs (CRPs) Challenges Responses

❖ Or, responses kept secret

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SLIDE 11

PUFs at a Glance DATE 2014

Design Considerations for Silicon PUFs

❖ Outputs determined by uncorrelated variation ❖ Random dopant fluctuations and small devices ❖ Balanced parasitics and wire lengths to avoid bias

5

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SLIDE 12

PUFs at a Glance DATE 2014

Design Considerations for Silicon PUFs

❖ Outputs determined by uncorrelated variation ❖ Random dopant fluctuations and small devices ❖ Balanced parasitics and wire lengths to avoid bias ❖ Variation and noise hard to separate ❖ Mask unreliable outputs ❖ Majority voting ❖ Error correction

5

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SLIDE 13

PUFs at a Glance DATE 2014

Design Considerations for Silicon PUFs

❖ Outputs determined by uncorrelated variation ❖ Random dopant fluctuations and small devices ❖ Balanced parasitics and wire lengths to avoid bias ❖ Variation and noise hard to separate ❖ Mask unreliable outputs ❖ Majority voting ❖ Error correction ❖ Secure

5

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SLIDE 14

PUFs at a Glance DATE 2014

Security Considerations

❖ Assumed capabilities of adversary ❖ Observe CRPs ❖ Measure side channels ❖ Disassemble and probe chip

6

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SLIDE 15

PUFs at a Glance DATE 2014

Security Considerations

❖ Assumed capabilities of adversary ❖ Observe CRPs ❖ Measure side channels ❖ Disassemble and probe chip ❖ Possible results of attacks ❖ DOS by increasing error rate of CRPs ❖ Train parametric model to predict responses ❖ Clone with another instance of PUF

6

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SLIDE 16

PUFs at a Glance DATE 2014

Security Considerations

❖ Assumed capabilities of adversary ❖ Observe CRPs ❖ Measure side channels ❖ Disassemble and probe chip ❖ Possible results of attacks ❖ DOS by increasing error rate of CRPs ❖ Train parametric model to predict responses ❖ Clone with another instance of PUF

6

2nd talk of session

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SLIDE 17

PUFs at a Glance DATE 2014

Security Considerations

❖ Assumed capabilities of adversary ❖ Observe CRPs ❖ Measure side channels ❖ Disassemble and probe chip ❖ Possible results of attacks ❖ DOS by increasing error rate of CRPs ❖ Train parametric model to predict responses ❖ Clone with another instance of PUF

6

3rd talk of session

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SLIDE 18

PUFs at a Glance DATE 2014

Security Considerations

❖ Assumed capabilities of adversary ❖ Observe CRPs ❖ Measure side channels ❖ Disassemble and probe chip ❖ Possible results of attacks ❖ DOS by increasing error rate of CRPs ❖ Train parametric model to predict responses ❖ Clone with another instance of PUF

6

4th talk of session

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SLIDE 19

PUFs at a Glance DATE 2014

Weak vs Strong PUFs

Weak PUFs

7

Strong PUFs

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SLIDE 20

PUFs at a Glance DATE 2014

Weak vs Strong PUFs

Weak PUFs

7

Strong PUFs

❖ Few/one challenges ❖ Many challenges

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SLIDE 21

PUFs at a Glance DATE 2014

Weak vs Strong PUFs

Weak PUFs

7

Strong PUFs

❖ Few/one challenges ❖ Responses remain internal ❖ Perfect internal error

correction

❖ Many challenges ❖ Public CRP interface ❖ Error correction outside

PUF is possible

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SLIDE 22

PUFs at a Glance DATE 2014

Weak vs Strong PUFs

Weak PUFs

7

Strong PUFs

❖ Few/one challenges ❖ Responses remain internal ❖ Perfect internal error

correction

❖ Attacks: Cloning and invasive

reading of responses

❖ Many challenges ❖ Public CRP interface ❖ Error correction outside

PUF is possible

❖ Attacks: Modeling attacks

and protocol attacks

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SLIDE 23

PUFs at a Glance DATE 2014

Weak vs Strong PUFs

Weak PUFs

7

Strong PUFs

❖ Few/one challenges ❖ Responses remain internal ❖ Perfect internal error

correction

❖ Attacks: Cloning and invasive

reading of responses

❖ Use cases: New form of key

storage

❖ Many challenges ❖ Public CRP interface ❖ Error correction outside

PUF is possible

❖ Attacks: Modeling attacks

and protocol attacks

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SLIDE 24

PUFs at a Glance DATE 2014

Weak vs Strong PUFs

Weak PUFs

7

Strong PUFs

❖ Few/one challenges ❖ Responses remain internal ❖ Perfect internal error

correction

❖ Attacks: Cloning and invasive

reading of responses

❖ Use cases: New form of key

storage

❖ Many challenges ❖ Public CRP interface ❖ Error correction outside

PUF is possible

❖ Attacks: Modeling attacks

and protocol attacks

❖ Use cases: New cryptographic

primitive

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SLIDE 25

PUFs at a Glance DATE 2014

Weak vs Strong PUFs

Weak PUFs

7

Strong PUFs

❖ Few/one challenges ❖ Responses remain internal ❖ Perfect internal error

correction

❖ Attacks: Cloning and invasive

reading of responses

❖ Use cases: New form of key

storage

❖ Many challenges ❖ Public CRP interface ❖ Error correction outside

PUF is possible

❖ Attacks: Modeling attacks

and protocol attacks

❖ Use cases: New cryptographic

primitive

❖ Weak and strong are two PUF subclasses among many ❖ Controlled PUFs ❖ Public PUFs ❖ SIMPL, etc

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SLIDE 26

PUFs at a Glance DATE 2014

Overview

  • 1. Brief introduction to PUFs
  • 2. Weak PUFs and applications
  • 3. Strong PUFs and applications
  • 4. Conclusions

8

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PUFs at a Glance DATE 2014

Examples of Weak PUFs

❖ Using custom circuits ❖ Drain currents [Lofstrom et al. ’02] ❖ Capacitive coating PUF [Tuyls et al. ’06] ❖ Cross-coupled devices [Su et al. ’07] ❖ Sense amps [Bhargava et al. ’10] ❖ Using existing circuits ❖ Clock skew [Yao et al.’13] ❖ Flash latency [Prabhu et al. ‘11] ❖ Power-up SRAM state [Guajardo et al. ’07, Holcomb et al. ’07]

9

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SLIDE 28

PUFs at a Glance DATE 2014

Examples of Weak PUFs

❖ Using custom circuits ❖ Drain currents [Lofstrom et al. ’02] ❖ Capacitive coating PUF [Tuyls et al. ’06] ❖ Cross-coupled devices [Su et al. ’07] ❖ Sense amps [Bhargava et al. ’10] ❖ Using existing circuits ❖ Clock skew [Yao et al.’13] ❖ Flash latency [Prabhu et al. ‘11] ❖ Power-up SRAM state [Guajardo et al. ’07, Holcomb et al. ’07]

9

"SRAM PUF" "PUF" Research Mentions by Year Year

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SLIDE 29

PUFs at a Glance DATE 2014

Applications of Weak PUFs

❖ Identification ❖ Authentication ❖ Secret key ❖ Random number generation

10

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SLIDE 30

PUFs at a Glance DATE 2014

Applications of Weak PUFs

❖ Identification ❖ Authentication ❖ Secret key ❖ Random number generation

10

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PUFs at a Glance DATE 2014

SRAM Power-up State

Utilize inherent power-up bias of each SRAM cell

11

A B

WL BL BLB 0.4 0.8 1.2 2 4 6 8 10 Voltage Time [ns] VDD A B VDD

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PUFs at a Glance DATE 2014

SRAM Power-up State

Utilize inherent power-up bias of each SRAM cell

11 ❖ Challenge: c (selects n cells)

A B

WL BL BLB 0.4 0.8 1.2 2 4 6 8 10 Voltage Time [ns] VDD A B VDD

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SLIDE 33

PUFs at a Glance DATE 2014

SRAM Power-up State

Utilize inherent power-up bias of each SRAM cell

11 ❖ Challenge: c (selects n cells) ❖ Responses: r ∈ 2n

(power-up state of n cells)

A B

WL BL BLB 0.4 0.8 1.2 2 4 6 8 10 Voltage Time [ns] VDD A B VDD

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SLIDE 34

PUFs at a Glance DATE 2014

SRAM Power-up State

Utilize inherent power-up bias of each SRAM cell

11 ❖ Challenge: c (selects n cells) ❖ Responses: r ∈ 2n

(power-up state of n cells)

❖ Disorder/randomness: Threshold

variation of transistors in SRAM cell

A B

WL BL BLB 0.4 0.8 1.2 2 4 6 8 10 Voltage Time [ns] VDD A B VDD

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SLIDE 35

PUFs at a Glance DATE 2014

SRAM Power-up State

Utilize inherent power-up bias of each SRAM cell

11 ❖ Challenge: c (selects n cells) ❖ Responses: r ∈ 2n

(power-up state of n cells)

❖ Disorder/randomness: Threshold

variation of transistors in SRAM cell

A B

WL BL BLB

[Holcomb et al., ’07]

0.4 0.8 1.2 2 4 6 8 10 Voltage Time [ns] VDD A B VDD

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SLIDE 36

PUFs at a Glance DATE 2014

Enroll PUF

Weak PUF as Secret Key

12

Weak PUF

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SLIDE 37

PUFs at a Glance DATE 2014

Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r)

12

Weak PUF

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PUFs at a Glance DATE 2014

Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r) ❖ Derive public error

correcting data h for r

❖ Key k = Decode(r ⊕ h)

12

Weak PUF

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PUFs at a Glance DATE 2014

Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r) ❖ Derive public error

correcting data h for r

❖ Key k = Decode(r ⊕ h) ❖ Store h with PUF ❖ Disable access to response r

12

Weak PUF

  • h
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SLIDE 40

PUFs at a Glance DATE 2014

Generate Key in Field Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r) ❖ Derive public error

correcting data h for r

❖ Key k = Decode(r ⊕ h) ❖ Store h with PUF ❖ Disable access to response r

12

Weak PUF

  • h
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SLIDE 41

PUFs at a Glance DATE 2014

Generate Key in Field Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r) ❖ Derive public error

correcting data h for r

❖ Key k = Decode(r ⊕ h) ❖ Store h with PUF ❖ Disable access to response r

12

c

Weak PUF

  • h
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SLIDE 42

PUFs at a Glance DATE 2014

Generate Key in Field Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r) ❖ Derive public error

correcting data h for r

❖ Key k = Decode(r ⊕ h) ❖ Store h with PUF ❖ Disable access to response r ❖ Apply c, obtain r’ ⊕ h ❖ Key k = Decode(r’ ⊕ h)

12

c

Weak PUF

  • h
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SLIDE 43

PUFs at a Glance DATE 2014

Generate Key in Field Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r) ❖ Derive public error

correcting data h for r

❖ Key k = Decode(r ⊕ h) ❖ Store h with PUF ❖ Disable access to response r ❖ Apply c, obtain r’ ⊕ h ❖ Key k = Decode(r’ ⊕ h)

12

k is reliable key

c

Weak PUF

  • h
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SLIDE 44

PUFs at a Glance DATE 2014

Generate Key in Field Enroll PUF

Weak PUF as Secret Key

❖ Learn CRP (c,r) ❖ Derive public error

correcting data h for r

❖ Key k = Decode(r ⊕ h) ❖ Store h with PUF ❖ Disable access to response r ❖ Apply c, obtain r’ ⊕ h ❖ Key k = Decode(r’ ⊕ h)

❖ Reliable unclonable key for crypto ❖ Assumes that r cannot be read in field

12

k is reliable key

c

Weak PUF

  • h
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SLIDE 45

PUFs at a Glance DATE 2014

Overview

  • 1. Brief introduction to PUFs
  • 2. Weak PUFs and applications
  • 3. Strong PUFs and applications
  • 4. Conclusions

13

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SLIDE 46

PUFs at a Glance DATE 2014

Examples of Strong PUFs

❖ Optical PUF [Pappu et al. ’02] ❖ Arbiter PUF [Gassend et al. ’02, Lim et al. ’05] ❖ Bistable Ring PUF [Chen et al. ’11] ❖ Low-power current-based PUF

[Majzoobi et al. ’11]

14

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SLIDE 47

PUFs at a Glance DATE 2014

Examples of Strong PUFs

❖ Optical PUF [Pappu et al. ’02] ❖ Arbiter PUF [Gassend et al. ’02, Lim et al. ’05] ❖ Bistable Ring PUF [Chen et al. ’11] ❖ Low-power current-based PUF

[Majzoobi et al. ’11]

14

"Arbiter PUF" "PUF" Research Mentions by Year Year

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SLIDE 48

PUFs at a Glance DATE 2014

Strong PUF Protocols

❖ Identification/Authentication (1) ❖ Key Exchange (2,3) ❖ Oblivious transfer (4,3,5,6) — enables secure two-party computation ❖ Bit commitment (3,5,6,7,8) — enables zero-knowledge proofs ❖ Combined key exchange and authentication (9) 15

(1) R. Pappu et al, Science 2002 (2) M.v.Dijk, US Patent 2,653,197, 2004 (3) C. Brzuska et al, CRYPTO 2011 (4) U. Rührmair, TRUST 2010 (5,6) U. Rührmair, M.v.Dijk, CHES 2012 and JCEN 2013 (7) U. Rührmair, M.v. Dijk, Cryptology ePrint Archive, 2012 (8) Ostrovsky et al., EUROCRYPT 2013 (9) Tuyls and Skoric, Strong Authentication with Physical Unclonable Functions, Springer 2007

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SLIDE 49

PUFs at a Glance DATE 2014

Strong PUF Protocols

❖ Identification/Authentication (1) ❖ Key Exchange (2,3) ❖ Oblivious transfer (4,3,5,6) — enables secure two-party computation ❖ Bit commitment (3,5,6,7,8) — enables zero-knowledge proofs ❖ Combined key exchange and authentication (9) 15

(1) R. Pappu et al, Science 2002 (2) M.v.Dijk, US Patent 2,653,197, 2004 (3) C. Brzuska et al, CRYPTO 2011 (4) U. Rührmair, TRUST 2010 (5,6) U. Rührmair, M.v.Dijk, CHES 2012 and JCEN 2013 (7) U. Rührmair, M.v. Dijk, Cryptology ePrint Archive, 2012 (8) Ostrovsky et al., EUROCRYPT 2013 (9) Tuyls and Skoric, Strong Authentication with Physical Unclonable Functions, Springer 2007

5th talk of session

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SLIDE 50

PUFs at a Glance DATE 2014

Strong PUF Protocols

❖ Identification/Authentication (1) ❖ Key Exchange (2,3) ❖ Oblivious transfer (4,3,5,6) — enables secure two-party computation ❖ Bit commitment (3,5,6,7,8) — enables zero-knowledge proofs ❖ Combined key exchange and authentication (9) 15

(1) R. Pappu et al, Science 2002 (2) M.v.Dijk, US Patent 2,653,197, 2004 (3) C. Brzuska et al, CRYPTO 2011 (4) U. Rührmair, TRUST 2010 (5,6) U. Rührmair, M.v.Dijk, CHES 2012 and JCEN 2013 (7) U. Rührmair, M.v. Dijk, Cryptology ePrint Archive, 2012 (8) Ostrovsky et al., EUROCRYPT 2013 (9) Tuyls and Skoric, Strong Authentication with Physical Unclonable Functions, Springer 2007

5th talk of session

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SLIDE 51

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

16

[D. Lim et al., ’05]

Q

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SLIDE 52

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages)

16

[D. Lim et al., ’05]

Q

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SLIDE 53

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages)

16

[D. Lim et al., ’05]

0 0 … 0 0

Q

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SLIDE 54

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages)

16

[D. Lim et al., ’05]

0 0 … 0 0

Q

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SLIDE 55

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

0 0 … 0 0

Q

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SLIDE 56

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

0 0 … 0 0

S R time voltage

Q

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SLIDE 57

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

Q=1

0 0 … 0 0

S R time voltage

Q

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SLIDE 58

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

Q=1 S R time voltage

Q

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SLIDE 59

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

Q=1

0 1 … 1 0

S R time voltage

Q

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SLIDE 60

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

Q=1

0 1 … 1 0

S R time voltage

Q

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SLIDE 61

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

Q=1

0 1 … 1 0

R S voltage time S R time voltage

Q

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SLIDE 62

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown)

16

[D. Lim et al., ’05]

Q=1 Q=0

0 1 … 1 0

R S voltage time S R time voltage

Q

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SLIDE 63

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown) ❖ Disorder/randomness: Delays in the

subcomponents

16

[D. Lim et al., ’05]

Q=1 Q=0

0 1 … 1 0

R S voltage time S R time voltage

Q

slide-64
SLIDE 64

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown) ❖ Disorder/randomness: Delays in the

subcomponents

16

[D. Lim et al., ’05]

Q=1 Q=0

0 1 … 1 0

R S voltage time S R time voltage

❖ Assumes that model cannot be created by observing CRPs ❖ But basic arbiter PUF susceptible to additive delay model

Q

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SLIDE 65

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown) ❖ Disorder/randomness: Delays in the

subcomponents

16

[D. Lim et al., ’05]

Q=1 Q=0

0 1 … 1 0

R S voltage time S R time voltage

❖ Assumes that model cannot be created by observing CRPs ❖ But basic arbiter PUF susceptible to additive delay model

Q

slide-66
SLIDE 66

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown) ❖ Disorder/randomness: Delays in the

subcomponents

16

[D. Lim et al., ’05]

Q=1 Q=0

0 1 … 1 0

R S voltage time S R time voltage

❖ Assumes that model cannot be created by observing CRPs ❖ But basic arbiter PUF susceptible to additive delay model

Q

slide-67
SLIDE 67

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown) ❖ Disorder/randomness: Delays in the

subcomponents

16

[D. Lim et al., ’05]

Q=1 Q=0

0 1 … 1 0

R S voltage time S R time voltage

❖ Assumes that model cannot be created by observing CRPs ❖ But basic arbiter PUF susceptible to additive delay model

[G. Suh et al., ’07] [M. Majzoobi et al., ’08]

Q

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SLIDE 68

PUFs at a Glance DATE 2014

S R 1 1 1 1 1 1 1 1

Arbiter PUF

❖ Challenges: ci ∈ 2m (m= num stages) ❖ Responses: ri ∈ 2n (n=1 shown) ❖ Disorder/randomness: Delays in the

subcomponents

16

[D. Lim et al., ’05]

Q=1 Q=0

0 1 … 1 0

R S voltage time S R time voltage

❖ Assumes that model cannot be created by observing CRPs ❖ But basic arbiter PUF susceptible to additive delay model

[G. Suh et al., ’07] [M. Majzoobi et al., ’08]

Q

❖ XOR Arbiter PUF resists

additive model

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SLIDE 69

PUFs at a Glance DATE 2014

Enroll PUF

Authentication using Strong PUF

17

Strong PUF

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SLIDE 70

PUFs at a Glance DATE 2014

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges

17

Strong PUF

slide-71
SLIDE 71

PUFs at a Glance DATE 2014

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

Strong PUF

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SLIDE 72

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

Strong PUF

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SLIDE 73

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

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SLIDE 74

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

Strong PUF

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SLIDE 75

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

c0

Strong PUF

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SLIDE 76

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

c0 r0’

Strong PUF

slide-77
SLIDE 77

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

c0 r0’

Authenticate r0 ≈ r0’ ? Strong PUF

slide-78
SLIDE 78

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

17

c0 r0’

Authenticate r0 ≈ r0’ ? Strong PUF

slide-79
SLIDE 79

PUFs at a Glance DATE 2014

(c0,r0) (c1,r1) (c2,r2) …

Enroll PUF

Authentication using Strong PUF

❖ Choose random challenges ❖ Apply and store private CRPs

❖ No need to hide responses if PUF cannot be

modeled

17

c0 r0’

Authenticate r0 ≈ r0’ ? Strong PUF

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SLIDE 80

PUFs at a Glance DATE 2014

Overview

  • 1. Brief introduction to PUFs
  • 2. Weak PUFs and applications
  • 3. Strong PUFs and applications
  • 4. Conclusions

18

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SLIDE 81

PUFs at a Glance DATE 2014

Review

19

❖ PUFs are exciting new security primitive based on

physical disorder

❖ Desirable properties but also limitations ❖ Arms race between designing and breaking

slide-82
SLIDE 82

PUFs at a Glance DATE 2014

Review

19

❖ PUFs are exciting new security primitive based on

physical disorder

❖ Desirable properties but also limitations ❖ Arms race between designing and breaking

  • 1. PUFs at a Glance
  • 2. Modeling attacks
  • 3. Modeling attacks using side-channel information
  • 4. Invasive attacks
  • 5. Requirements for secure PUF protocols
  • 6. Forward-looking trends and challenges

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