Secure Authentication Scheme withAnonymity for WirelessCommunicationsSecure Authentication Scheme withAnonymity for WirelessCommunications
Speaker : Hong-Ji Wei
Date : 2012-12-08
OutlineOutline
1. Introduction
2. Review of Wu et al.’s scheme
3. Weakness of Wu et al.’s scheme
4. Improved Scheme
5. Security Analysis
6. Conclusion
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1. Introduction1. Introduction
人
In recent years, many authors proposed the anonymousauthentication scheme for wireless communications.
In 2004, Zhu and Ma proposed an authenticationscheme with anonymity for wireless communications.However, in 2006, Lee, Hwang and Laio pointed outthat Zhu-Ma’s scheme exists some weaknesses andproposed the improved scheme to overcome theseweaknesses in Zhu-Ma’s scheme.
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1. Introduction1. Introduction
In 2008, Wu, Lee and Tsaur pointed out that Lee et al’sscheme still exists weakness of anonymity andbackward secrecy. Therefore, they also proposed animproved scheme to improve the weaknesses in Lee etal.’s scheme.
In 2009, Zeng et al and Lee et al found out that Wu etal.’s scheme still not protect the anonymity of user.However, they did not propose the scheme to improveit.
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1. Introduction1. Introduction
In 2009, Chang et al. also pointed out that Wu et al’sscheme exists two weaknesses, which failed toachieve the anonymity and prevent impersonationattack. At the same time, they also proposed theimproved scheme to overcome these weaknesses.However, it’s unfortunately, their proposed scheme stillnot efficiently overcome these weaknesses.
In this paper, we will analyze Wu et al.’s scheme andpropose a secure anonymous authentication scheme toimprove the security weaknesses in Wu at al.’s scheme.
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2. Review of Wu et al.’s scheme2. Review of Wu et al.’s scheme
Notations
MU : Mobile User
HA : Home Agent of a mobile user
FA : Foreign Agent of the network
IDA: Identity of A
TA : Timestamp of A
CertA : Certificate of A
(X)K : Symmetric Encryption
EK(X) : Asymmetric Encryption
h(X) : Hash X using hash function
PWA : Password of A
PA : Public key of A
SA : Private key of A
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2. Review of Wu et al.’s scheme2. Review of Wu et al.’s scheme
This scheme can be divided into three phases
1.Initial Phase
MU registers with HA through secure channel.
2.First Phase
FA authenticates MU through HA and establishes a session
key with MU.
3.Second Phase
MU updates the session key with FA.
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2. Review of Wu et al.’s scheme2. Review of Wu et al.’s scheme
Initial Phase
MU
HA
Secure Channel
Secure Channel
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2. Review of Wu et al.’s scheme2. Review of Wu et al.’s scheme
First Phase
MU
FA
HA
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2. Review of Wu et al.’s scheme2. Review of Wu et al.’s scheme
Second Phase
In order to enhance the efficiency, while MU stayswith the same FA, the new session key ki can be derivedfrom the unexpired previous secret knowledge xi−1 and afixed secret x as
MU
FA
Session key update
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3. Weakness of Wu et al.’s scheme3. Weakness of Wu et al.’s scheme
Anonymity
Attacker
MU
FA
HA
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3. Weakness of Wu et al.’s scheme3. Weakness of Wu et al.’s scheme
Impersonation attack
MU
FA
HA
PWMU *
Attacker
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4. Improved scheme4. Improved scheme
Registration Phase
MU
HA
Secure Channel
Secure Channel
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Authentication and establishment session key phase
4. Improved scheme4. Improved scheme
MU
FA
HA
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4. Improved scheme4. Improved scheme
Session key update phase
In order to enhance the efficiency, while MU stayswith the same FA, the new session key ki can be derivedfrom the unexpired previous secret knowledge xi−1 and afixed secret x as
MU
FA
Session key update
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Password change phase
MU
FA
HA
4. Improved scheme4. Improved scheme
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5. Security Analysis5. Security Analysis
Anonymity
Attacker
MU
FA
HA
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5. Security Analysis5. Security Analysis
Impersonation Attack
MU
FA
HA
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5. Security Analysis5. Security Analysis
Comparison Table
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6. Conclusion6. Conclusion
In this paper, we propose the secure anonymous auth-entication scheme which not only improves the abovementioned weaknesses in Wu et al.’s scheme, but alsoprovides the extra function of changing password formobile users.
From our security analysis, we find out that ourproposed scheme indeed can improve all of theweaknesses in Wu et al.’s scheme and also achieve ourexpected efficiency.
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Many thanks for your listeningMany thanks for your listening
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