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Three-Party Authenticated Key Agreements and Its Applications- PCSs Roaming Protocol

李添福 (Tian-Fu Lee)國立成功大學資訊工程博士

Cryptography/ Network security/ Wireless networks communication/ Algorithmic graph theory/ Dat

abase and data engineering

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Outlines

Three-Party Authenticated Key Agreements (3PAKA) Applications

Portable Communication Systems (PCSs) Roaming Protocol RFID Protocol E-Payment Protocol Electronic Medical Record Security and Privacy Vehicular Mobile Network

Proposed PCSs Roaming Protocol Delegation-Based Authentication Protocol for PCSs Security discussion Computational comparison & Experimental Results

Conclusions

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Three-Party Authenticated Key Agreements

An authenticated key agreement protocol is an interactive method for two or more parties to determine session keys based on their secret keys or public/private keys.

AuthenticationAuthentication

Key agreement / key exchangeSK

Secure communication

Trusted server

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Portable Communication Systems Roaming Protocol

Mobile Station

Visited Network Home NetworkPDA

cellular phone

notebook

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RFID Protocol

Tag Reader Database Server

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E-Payment Protocol

BuyerSeller

E-Bank

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醫療資訊安全 - 電子病歷安全與隱私(Electronic Medical Record Security and Privacy)

IC card

Hospital

政府衛生行政單位電子病歷 Database

健保機關

一般民眾

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Vehicular Mobile Network

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Proposed PCSs Roaming Protocol

Delegation-Based Authentication Protocol for PCSs

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Delegation-Based Authentication Protocol for PCSs

RegistrationOn-line authentication processi-th Off-line authentication process

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Delegation-Based Authentication Protocol for PCSs

MS VN

HN

Delegation ((x),K)

(x,v=gx)

Public key (v)

Proxy signature

Verify the signature by v

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On-line authentication process

Sing(msg.),K

VerifyK

MS (,K) VN (KVH; pk:v) HN (,KVH)

KIDMS

SK,h(token)

SK, token

Obtain SK Obtain SK

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i-th Off-line authentication process

ESKi(tokeni,h(tokeni+1))

Verify tokeni

Keep h(tokeni+1) Compute SKi+1

MS (SKi, tokeni) VN (SKi, h(tokeni)) HN

Compute SKi+1

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comparison

Previous Scheme: tokeni and tokeni+1 are independent. HN can forge tokeni Have not non-repudiation Charge Problem :

Mobile users deny has used services and refuse to pay. Overcharge mobile users for services that he did not request.

[IEEE Trans. Wireless Commun. 2005] Proposed Scheme:

All tokeni are chained by backward hash-chain and are decided by MS. HN cannot forge tokeni Have non-repudiation Pre-Compute and reduce the computational cost in MS.

[IEEE Trans. Wireless Commun. 2009]

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i-th Off-line authentication process

ESKi(tokeni)Verify tokeni

Keep tokeni = h(tokeni+1) Compute SKi+1

MS (SKi, tokeni) VN (SKi, h(tokeni)) HN

Compute SKi+1

Pre-compute and store h(1)(n1),

h(2)(n1) (=tokenn),

…, h(n)(n1)(=token2),

h(n+1)(n1)(=token1) token1

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Security Discussion

GSM MGSM Public-keybased scheme

Lee & Yeh'sScheme

ProposedScheme

Identity privacy No No No Yes Yes

Non-repudiation No No Yes No Yes

Mutual-authen.(MS-VN)

No No Yes Yes Yes

Easy key management

Yes Yes No Yes Yes

Low computational load

Yes Yes No Yes Yes

Good commu. efficiency

Yes Yes No Yes Yes

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Computational comparison of MS

*: Can be pre-computed in this entry.

hash function secret-key computation(encryption/decryption)

public-key computation(signature/verification)

GSM 2(n+1) 1(n+1) 0

MGSM 1(n+1) 1(n+1) 0

Public-key based scheme 0 0 2n

Lee & Yeh's scheme

On-line 2 1 1Pre.*

Off-line 3n n 0

Proposed scheme On-line (n+1)Pre.*+2 1 1Pre.*

Off-line n n 0

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Experimental Results

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

Pre-comp.

on-line off-line1 off-line2 off-line3 off-line4 off-line5

period

time(

ms)

Lee and Yeh's Protocol

Proposed Protocol

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Experimental Results

84.2

84.22

84.24

84.26

84.28

84.3

84.32

84.34

84.36

84.38

84.4

Pre-comp.

on-line off-line1 off-line2 off-line3 off-line4 off-line5(Total)

period

time(

ms)

Lee and Yeh'sProtocol

Proposed Protocol

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Conclusions

Three-party authenticated key agreements and its applications

Proposed secure and efficient delegation-based authentication protocol for PCSs

Future researchesVehicular Mobile NetworkElectronic Medical Record Security and Privacy

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References

Lee, T.-F., Hwang, T. and Lin C.-L. “Enhanced Three-Party Encrypted Key Exchange without Server Public Keys,” Computers & Security, Volume: 23, Issue: 7, pp. 571-577, October, 2004.

Wen, H.-A., Lee, T.-F. and Hwang, T. “A Provably Secure Three-Party Password-based Authenticated Key Exchange Protocol Using Weil Pairing,” IEE Proc. Communications, Vol. 152, No. 2, pp. 138-143, April 2005.

Lee, T.-F., Liu, J.-L., Sung, M.-J., Yang, S.-B. and Chen, C.-M., “Communication-Efficient Three-Party Protocols for Authentication and Key Agreement”, Computers and Mathematics with Applications, Vol. 58, No, 4, pp.641-648, August, 2009.

Lee, T.-F., Chang, C.-C. and Hwang, T. “Private Authentication Techniques for the Global Mobility Network,” Wireless Personal Communications, Vol. 35,Issue: 4, pp. 329-336, December 2005.

Lee, W.-B. and Yeh, C.-K., “A new delegation-based authentication protocol for use in portable communication systems,” IEEE Trans. Wireless Commun., vol. 4, no.1, pp.57-64, January 2005.

Lee, T.-F., Chang, S.-H., Hwang, T. and Chong, S.-K., “Enhanced Delegation-Based Authentication Protocol for PCSs”, IEEE Trans. Wireless Commun., Vol.8, No. 5, pp. 2166-2171, May 2009.