The document outlines a secure communication mechanism for vehicular ad-hoc networks (VANETs). It discusses two existing approaches: (1) PACP, an efficient pseudonymous authentication-based conditional privacy protocol, and (2) a secure communication mechanism using self-generated pseudonyms. It also covers background concepts, notations, network models, and protocols for each approach. The goal is to preserve privacy and enable anonymous communication in VANETs while allowing for conditional access to identity.

1. Outline Secure Communication with Privacy
Introduction
Motivation
Preservation in VANET
Related Works
PACP [2]
Ankit Gupta
Secure Com-
munication in M.Tech 2nd Year
VANETs with
Self-Generated
Reg. No. 2011IS20
Pseudonym
Mechanism [3]
Department of Computer Science and Engineering
Observations
and Motilal Nehru National Institute of Technology Allahabad
Comparisons
Conclusion
November 19, 2012
References
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2. Outline
1 Introduction
Outline
2 Motivation
Introduction
Motivation
3 Related Works
Related Works
PACP [2] 4 PACP [2]
Secure Com-
munication in 5 Secure Communication in VANETs with Self-Generated
VANETs with
Self-Generated Pseudonym Mechanism [3]
Pseudonym
Mechanism [3]
Observations
6 Observations and Comparisons
and
Comparisons
7 Conclusion
Conclusion
References 8 References
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3. Introduction
Outline
Introduction
Motivation
Related Works
Ad-Hoc Network
PACP [2] Vehicular Ad-Hoc Network (VANET)
Secure Com-
munication in
Need of VANETs
VANETs with
Self-Generated Privacy Preservation in VANETs
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
References
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4. Motivation
Outline
Introduction
Motivation Tracking mechanisms are getting advanced.
Related Works Adversary can track a vehicle by observing its
PACP [2] communication and movement patterns.
Secure Com-
munication in Preserving privacy and anonymous communication inside
VANETs with
Self-Generated the VANET is a double-edged feature.
Pseudonym
Mechanism [3] Vehicles in VANET need conditional privacy.
Observations
and
Comparisons
Conclusion
References
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5. Related Works
Outline
Introduction Research works on authentication to ensure security in
Motivation VANET [5, 6].
Related Works
Vehicle Safety Communication Project (VSC) [7].
PACP [2]
Efficient Conditional Privacy Preservation (ECPP)
Secure Com-
munication in Protocol [4].
VANETs with
Self-Generated
Pseudonym
Public Key Infrastructure (PKI) is used in most of the
Mechanism [3]
schemes designed for anonymity in VANET.
Observations
and Existing schemes are not truly anonymous.
Comparisons
Conclusion
References
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6. Outline
Introduction
Motivation
Related Works
First Candidate Solution: PACP: An Efficient
PACP [2]
Pseudonymous Authentication-Based Conditional Privacy
Secure Com-
munication in Protocol [2].
VANETs with
Self-Generated
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
References
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7. Background Concepts
Outline
Introduction
Motivation
Related Works
Conditional Privacy
PACP [2] Bilinear Mapping [1]
Secure Com-
munication in
Identity-Based Encryption [1]
VANETs with
Self-Generated Elliptic Curve Discrete Logarithmic Problem (ECDLP)
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
References
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8. Network Model for VANET
Outline
Introduction
Motivation
Related Works
PACP [2]
Secure Com-
munication in
VANETs with
Self-Generated
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
References Figure: Network Model for VANET[2].
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9. Notations used in PACP and Publicly known
system parameters
Notation Description
ID The Identity of the vehicle
Ri The Identity of RSU Ri (also its public key)
Outline SR The Private key of RSU Ri
i
Introduction RTH Threshold value of the RSU
CertR Identity-based Certificate of RSU Ri
i
Motivation SIG (M; K ) ECC-based signature of using key K.
PMVD The Public Key of the MVD
Related Works SMVD The Private Key of the MVD
M Message
PACP [2] C Ciphertext
Secure Com-
munication in Table: Notations used in PACP.
VANETs with
Self-Generated
Pseudonym
Mechanism [3] e : G1 × G1 → G2
ˆ Mapping from an additive group G1 to a multiplicative group G2
P G1 P is a generator of G1
Observations PMVD = αP Public Key of MVD
and H : G1 → (0, 1)n H, H1 , H2 are publicly known hash functions
Comparisons H1 : G2 → (0, 1)n
H2 : (0, 1)n × (0, 1)n → (0, 1)n
Conclusion
References Table: Publicly known system parameters.
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10. PACP Protocols
Registration Protocol
Outline
Generation Protocol
Introduction Extraction Protocol
Motivation
Related Works
PACP [2]
Secure Com-
munication in
VANETs with
Self-Generated
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
Figure: State transition diagram for pseudonym generation in
References PACP[2].
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11. Anonymous Communication in PACP
Outline
Introduction
Motivation
Related Works
Encryption Protocol
PACP [2]
Secure Com-
Decryption Protocol
munication in
VANETs with Revocation Protocol
Self-Generated
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
References
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12. Outline
Introduction
Motivation
Related Works
PACP [2]
Second Candidate Solution: Secure Communication in
Secure Com- VANETs with Self-Generated Pseudonym Mechanism [3].
munication in
VANETs with
Self-Generated
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
References
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13. Background Concepts
Outline
Introduction
Motivation
Related Works
Identity-Based Encryption
PACP [2]
Secure Com-
Authorization Server
munication in
VANETs with Vehicle
Self-Generated
Pseudonym
Mechanism [3]
Observations
and
Comparisons
Conclusion
References
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14. Notations used in second candidate solution
Outline
Introduction
Notation Description
Motivation PRX /PUX Private/Public key of a vehicle X, X ∈ AS,V.
α Pseudonym of vehicle broadcasting
Related Works e() Weil pairing map
⊕ Operator of cyclic additive group G1
PACP [2] a·R R self adding a times, R ∈ G1
⊗ Operator of cyclic multiplicative group G2
Secure Com- tsv Timestamp of vehicle V.
munication in Ek (m) Symmetrical encryption by using the secret key k to
VANETs with encrypt the message m.
Self-Generated
Pseudonym
Mechanism [3] Table: Notations used in second candidate solution.
Observations
and
Comparisons
Conclusion
References
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15. Different Phases
Outline
Introduction
Motivation Broadcasting Phase
Related Works
Message Authentication Phase
PACP [2]
Secure Com- Revoking Vehicle Phase
munication in
VANETs with Online Secret Key Renewal Phase
Self-Generated
Pseudonym
Mechanism [3]
Recovering Identity Phase
Observations
and
Comparisons
Conclusion
References
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16. Observations from first candidate solution
Outline
Introduction
Motivation Hardness of ECDLP
Related Works
BLS Short Signature and Encryption
PACP [2]
Secure Com- Generation and Decryption Protocols
munication in
VANETs with Secure against linking attacks
Self-Generated
Pseudonym
Mechanism [3]
Multiple Pseudonyms
Observations
and
Comparisons
Conclusion
References
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17. Observations from second candidate solution
Outline
Introduction
Motivation Hardness of ECDLP
Related Works
Authentication
PACP [2]
Secure Com- Anonymity
munication in
VANETs with Unlinkability
Self-Generated
Pseudonym
Mechanism [3]
Non-Repudiation
Observations
and
Comparisons
Conclusion
References
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18. Comparison of both the solutions with ECPP
Outline
First Solution Second Solu- ECPP [4]
Introduction [2] tion [3]
Motivation Authentication YES YES YES
Anonymity YES YES YES
Related Works Unlinkability YES YES NO
Traceability YES YES YES
PACP [2] Integrity YES YES YES
Non-Repudiation YES YES YES
Secure Com-
munication in Revoking Vehicle FASTER FAST SLOW
VANETs with Resisting Replay Attack YES YES YES
Self-Generated Resisting Impersonation YES YES YES
Pseudonym Attack
Mechanism [3]
Observations
Table: Security comparisons.
and
Comparisons
Conclusion
References
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19. Comparison of both the candidate solutions
Outline
First Solution[2] Second Solution[3]
Introduction Pseudonym Generation Done at vehicle by communicat- Done at vehicle by communi-
ing with RSU each time. cating with the Authorization
Motivation
Server only once.
Related Works Vehicle’s Registration Done Offline. Vehicle to be Done Online. Registers at
physically present at MVD. Authorization Server via secure
PACP [2] channel.
Load at RSU MORE LESS
Secure Com- Communication Overhead in MORE LESS
munication in Network
VANETs with Extent of Anonymity SAME SAME
Self-Generated Resisting Compromised RSU at- YES NO
Pseudonym tack
Mechanism [3]
Secret Keys of Vehicle STATIC DYNAMIC
Observations
and Table: Comparison of two candidate solutions.
Comparisons
Conclusion
References
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20. Conclusion
Outline
Introduction
Different sides of the same coin.
Motivation
Related Works
Aims towards achieving anonymous communication with
PACP [2] conditional privacy in VANET.
Secure Com-
munication in
Second solution is an improvement over the first one in
VANETs with some respect.
Self-Generated
Pseudonym
Mechanism [3] Both can be merged to generate a better and efficient
Observations solution.
and
Comparisons
Conclusion
References
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21. References I
Outline
Introduction Boneh, D., and Franklin, M.
Motivation Identity-based encryption from the weil pairing.
Related Works
SIAM J. Comput. 32, 3 (Mar. 2003), 586–615.
PACP [2]
Secure Com- Huang, D., Misra, S., Verma, M., and Xue, G.
munication in
VANETs with Pacp: An efficient pseudonymous authentication-based
Self-Generated
Pseudonym conditional privacy protocol for vanets.
Mechanism [3]
Intelligent Transportation Systems, IEEE Transactions on
Observations
and 12, 3 (sept. 2011), 736 –746.
Comparisons
Conclusion
References
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22. References II
Outline Hwang, R. J., Hsiao, Y.-K., and Liu, Y.-F.
Introduction Secure communication scheme of vanet with privacy
Motivation preserving.
Related Works In Parallel and Distributed Systems (ICPADS), 2011 IEEE
PACP [2] 17th International Conference on (dec. 2011), pp. 654
Secure Com-
munication in
–659.
VANETs with
Self-Generated Lu, R., Lin, X., Zhu, H., Ho, P.-H., and Shen, X.
Pseudonym
Mechanism [3] Ecpp: Efficient conditional privacy preservation protocol for
Observations secure vehicular communications.
and
Comparisons In INFOCOM 2008. The 27th Conference on Computer
Conclusion Communications. IEEE (april 2008), pp. 1229 –1237.
References
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23. References III
Outline
Raya, M., and Hubaux, J.-P.
Introduction
Securing vehicular ad hoc networks.
Motivation J. Comput. Secur. 15, 1 (Jan. 2007), 39–68.
Related Works
Raya, M., Papadimitratos, P., and Hubaux, J.-P.
PACP [2]
Securing vehicular communications.
Secure Com-
munication in Wireless Communications, IEEE 13, 5 (october 2006), 8
VANETs with
Self-Generated –15.
Pseudonym
Mechanism [3] US Department of Transportation, N. H. T.
Observations
and
S. A.
Comparisons
Vehicle safety communication projects-final report.,
Conclusion
January 2008.
References
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