An Object Oriented Approach to an Identity Based Cryptosystem

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An Object Oriented Approach to an Identity Based
Cryptosystem
Computer Security and Cryptography
Group,Department of Computer Science,National
University of Ireland, Maynooth.

• Adam Duffy and Tom Dowlinghttp//crypto.cs.may.ie
  /

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Public Key Encryption(Sender)
Recipients Public Key Certificate
Recipients Public Key
Encrypted Message
Gentlemen don't read each others mail
Hgiqgo Asdf97u2 129afhg0 iqiaqnzi
Encryption
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Public Key Encryption(Recipient)
Recipients Private Key
Encrypted Message
Gentlemen don't read each others mail
Hgiqgo Asdf97u2 129afhg0 iqiaqnzi
Encryption
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Public Key Certificates

• Certification Authority (CA)
• One for each recipient

Typical Public/Private Key
8d668b07 d7880a85 4a8c573c e8e509be 3386bed5
e5d263df 35b7e67a 40c1def4 091f1a6e ba48ec75
d4e04f37 4d702298 de913019 c14728e9 13c164b0
908c81e8 e66bb283 78575f42 8013b001 50941ac8
0879c41f 8708d52e ba7d9f13 2cf755c6 5ce8fa76
03e80d0e bb86dcb2 93454af4 50a3eab2 f26bbe0f
48e32c57 c9e8c0b9 73ad44fe bb63b8a8 c339e63f
83969c64 23f64771 d0291323 ac8096d0 5126cb26
9256a876 de9eae7e a5d24dec ce6538c6 0639daac
dbef6341 781479a6 395bc34e 051c27b7 8eaa522a
3cc82897 08962e8f dcdbbc1a 2f3314f7 beaf13a0
652699ad 313b6d71 9065d0aa 482654fe 307bd817
f088fc37 86430478 2ea4a6fb ef50aaa5
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Identity Based Encryption(Sender)
Recipients Public Key recipient_at_company.com
Encrypted Message
Gentlemen don't read each others mail
Hgiqgo Asdf97u2 129afhg0 iqiaqnzi
Encryption
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Development Process

• Cryptographic vulnerability rare
• Implementation attacks frequent
• Modularisation
• Assertions
• Default Security
• Test, Fix, Test,
• Open Source

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Modularisation
g tate.pair(Q,sP)
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Modularisation

• Java Cryptographic Architecture (JCA)
• Message Digest
• MD5
• SHA
• Tiger
• Whirlpool

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Assertions

• Millers algorithm
• Division by zero
• rare event

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Default Security

• Minimum requirement
• 1024 bits
• Will not accept smaller values

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Test, Fix, Test,

• eXtreme Programming
• Simplicity
• Standards
• Unit tests
• Continuous integration
• Collective ownership

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Open Source

• Kerchoffs principle
• Implementation attacks
• Linuss Law

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Identity Based Signatures(Signer)
Gentlemen don't read each others mail
Signers Private Key
SecureHash
Encrypted Message Digest
Message Digest
8ahjhjkla
Jko2jjaliq3
Encryption
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Identity Based Signatures(Verifier)
Signers Public Key recipient_at_company.com
Jko2jjaliq3
8ahjhjkla
Decryption
Gentlemen don't read each others mail
SecureHash
8ahjhjkla
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Biometric IBS(Verifier)
Signers Public Key
Jko2jjaliq3
8ahjhjkla
Decryption
Gentlemen don't read each others mail
SecureHash
8ahjhjkla
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Biometric IBS
IBC JCA Provider
BIO-IBS
BF-IBE
BLS-IBS
Fuzzy Extractors
Pairings
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Smart Cards

• Private Key Generator (PKG)
• Java Card
• Portable
• Secure
• s Secret Key