LectureNote14-PublicKey

LectureNote14-PublicKey - P UBLIC K EY C RYPTOGRAPHY P...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: P UBLIC K EY C RYPTOGRAPHY P UBLIC K EY C RYPTOGRAPHY I NTRO . TO N UMBER T HEORY D IFFIE-H ELLMAN C RYPTOSYSTEM RSA C RYPTOSYSTEM O THER P UBLIC K EY C RYPTOSYSTEMS M ESSAGE D IGESTS AND C ERTIFICATES CS 556 - Computer Security - c circlecopyrt 2009 Colorado State University 1 / 93 Public Key Cryptosystem P UBLIC K EY C RYPTOGRAPHY I NTRO . TO N UMBER T HEORY D IFFIE-H ELLMAN C RYPTOSYSTEM RSA C RYPTOSYSTEM O THER P UBLIC K EY C RYPTOSYSTEMS M ESSAGE D IGESTS AND C ERTIFICATES CS 556 - Computer Security - c circlecopyrt 2009 Colorado State University 2 / 93 Traditional secret key cryptography uses a single key shared by both sender and receiver Problem How to share the key? Does not protect sender from the receiver forging a message & claiming that message is sent by sender, the two parties being equal Solution - public key / asymmetric key cryptosystem Goal of Public Key Crypto P UBLIC K EY C RYPTOGRAPHY I NTRO . TO N UMBER T HEORY D IFFIE-H ELLMAN C RYPTOSYSTEM RSA C RYPTOSYSTEM O THER P UBLIC K EY C RYPTOSYSTEMS M ESSAGE D IGESTS AND C ERTIFICATES CS 556 - Computer Security - c circlecopyrt 2009 Colorado State University 3 / 93 ... two parties communicating solely over a public channel and using only publicly known techniques can create a secure connection. Diffie, Hellman, New Directions in Cryptography, IEEE Transactions on Information Theory, Vol IT-22(6), Nov 1976. Public Key Cryptosystem P UBLIC K EY C RYPTOGRAPHY I NTRO . TO N UMBER T HEORY D IFFIE-H ELLMAN C RYPTOSYSTEM RSA C RYPTOSYSTEM O THER P UBLIC K EY C RYPTOSYSTEMS M ESSAGE D IGESTS AND C ERTIFICATES CS 556 - Computer Security - c circlecopyrt 2009 Colorado State University 4 / 93 Public-key (or two-key or asymmetric key) cryptography involves the use of two keys: a public-key, which may be known by anybody, and can be used to encrypt messages , and verify signatures a private-key, known only to the recipient, used to decrypt messages , and create signatures Public Key Cryptosystem P UBLIC K EY C RYPTOGRAPHY I NTRO . TO N UMBER T HEORY D IFFIE-H ELLMAN C RYPTOSYSTEM RSA C RYPTOSYSTEM O THER P UBLIC K EY C RYPTOSYSTEMS M ESSAGE D IGESTS AND C ERTIFICATES CS 556 - Computer Security - c circlecopyrt 2009 Colorado State University 5 / 93 First conceived by Diffie and Hellman in 1976 Rivest, Shamir and Adleman were first to describe a public key system in 1978 Merkle and Hellman published a different solution in...
View Full Document

Page1 / 18

LectureNote14-PublicKey - P UBLIC K EY C RYPTOGRAPHY P...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online