An Efficient and Practical Authenticated Communication Scheme for Vehicular Ad Hoc Networks
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Transcript of An Efficient and Practical Authenticated Communication Scheme for Vehicular Ad Hoc Networks
An Efficient and Practical Authenticated Communication Scheme for Vehicular Ad Hoc Networks
Source: IEEE Transactions on Vehicular Technology, Reviewing
Presenter: Yung-Chih Lu (呂勇志 )
Date: 2011/03/04
Outline
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Introduction Proposed Scheme Security Analysis Performance Analysis Conclusion Comment
Introduction (1/3)
Goal Message Authentication & Message
Encryption Against attack
Replay attackImpersonation attackOutsider attack
Saving resourcecomputation cost
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Introduction (2/3)
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Vehicular Ad Hoc Network (VANET)
RSC: Road Side Unit
Introduction (3/3)
The Functions of Proposed Scheme Traffic control schemes
Message Authentication Entertainment service scheme
Message Encryption
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Vehicle-RSU-Vehicle Communication
Proposed Scheme for Traffic Control (1/2)
6V: Vehicular M: Message TVi: Timestamp Kvi: A pre-shared keyx: RSU’s private key t: Random number H(): one way hash functionQ: base point over Elliptic Curve X= x . Q
Vi
(IDVi, IDVj, M, TVi, Kvi⊕ H(M||TVi))
VjRSU
1.Computes K’Vi =H(IDVi || x)2. Decrypts Kvi⊕ H(M||TVi)3.
4.Checks M,Tvi
5. Selects t ∈ Z*n
6. Computes T= t . Q = (x1,y1) r= x1 mod n s= t-1 . [H(M||TR)+x .t]7.Broadcast (IDR, IDVj, M, (r,s), TR )
1.Computes (s-1 . H(M||TR)) . Q+s-1 . r . X)= (x1’,y1
’)2. Verifies r’ = r r’= x1’ mod n
CSESPP Scheme
Proposed Scheme for Entertainment Service (2/2)
7V: Vehicular Reg: Request message TVi: Timestamp Kvi: A pre-shared keyES: Entertainment Service R: Random number H(): one way hash functionCSESPP: Communication Scheme for Entertainment Services with Privacy Preservation
Vi
(IDVi, Reg, TVi, H(Kvi||TVi))
RSU
1.Computes K’Vi =H(Kvi||TVi)2. Verifies H(K’vi||TVi) =H(Kvi||TVi) 3. R∈ Z*
n
4. Computes SKi= H(Kvi||R) {ESKi(ES,R) ,R}
1.Computes SKi =H(Kvi||R)2. Decrypts ESKi(ES,R) 3. Check R
K’Vi =H(IDVi || x)
Security Analysis (1/1)
Against attack Outsider attack
Secret key Impersonation attack
Secret key Replay attack
Timestamp
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Performance Analysis (1/1)
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Comparisons Table
TEC_Mul: the operation time of point multiplication on the elliptic curve functionTexp: the operation time of the modular exponentiationTmul: the operation time of the modular multiplication
Conclusion
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A vehicle only needs to share one session key with RSU to communicate with the other vehicles.
The proposed scheme is more efficient than other scheme.
Comment (1/2)
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本文主要貢獻簡述: 所有認證與加密工作皆透過公認第三方 (RSU) 來進行 ,
搭配 ECDSA 簽章,降低 Computation cost 。優點:
提出橢圓曲線的 point multiplication 比 modular exponentiation 更有效率的概念,來降低computation cost 。
缺點: 錯字都集中在 proposed scheme 。 Security Analysis 缺乏證明。 當 Vehicular 周圍無 RSU 時,則無法進行
authentication 及 encryption 。
Comment (2/2)
作者需進一步說明 : 請解釋在 Entertainment Service 中,使用隨機值 R
的用意。明顯錯誤 ( 含 typos):
Page6, 倒數第 3 行 S 應改成 M Page16, Figure1, 第 8 行 H’(IDVi||x) =⊕ H(IDVi||x) 應
改成 H’(M||TVi) =H(M||TVi) Page16, Figure1, 第 13 行 x . t 應改成 x . r Page18, Figure2, 第 5 行 K’Vi =H(Kvi||TVi) 應改成 K’Vi
=H(IDVi || x)
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Li et al.’s Scheme for Traffic Control (1/2)
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Vi Vj
1.Computes 1.Decrypts the message by Ht(SK)2.Computes
3.check
Vehicle-to-Vehicle Communication