Tcs forum the 9th of november 2007
Download
1 / 2

TCS Forum the 9th of November 2007 - PowerPoint PPT Presentation


  • 91 Views
  • Uploaded on

Professor Jorma Jormakka PhD in Mathematics University of Helsinki 2000 - 2004 Professor, Networking laboratory, Department of Electrical Engineering, TKK 2000 Professor, National Defence University On existence of polynomial-time algorithms for the Merkle-Hellman knapsack problem.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' TCS Forum the 9th of November 2007' - evangeline-dillard


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Tcs forum the 9th of november 2007

Professor Jorma Jormakka

PhD in Mathematics University of Helsinki

2000 - 2004 Professor, Networking laboratory,

Department of Electrical Engineering, TKK

2000 Professor, National Defence University

On existence of polynomial-time algorithms for the Merkle-Hellman knapsack problem

TCS Forum the 9th of November 2007


Merkle hellman knapsack cryptosystem
Merkle-Hellman Knapsack Cryptosystem

  • An asymmetric-key cryptosystem

  • Unlike RSA, the public key is used only for encryption, and the private key is used only for decryption.

  • The Merkle-Hellman system is based on the subset sum problem: given a list of numbers and a third number, which is the sum of a subset of these numbers, determine the subset.

  • Subset sum problem is known to be NP-complete.

  • If the set of numbers is super-increasing, that is, each element of the set is greater than the sum of all the numbers before it, the problem is 'easy' and solvable in polynomial time with a simple greedy algorithm.

  • Private key is composed of a super-increasing set of numbers, and a multiplier and a modulus, which are used to convert the easy subset sum problem to a difficult one.

  • Public key is the difficult subset sum problem.


ad