Dismiss
InnovationQ will be updated on Sunday, Jan. 21, from 9am - 11am ET. You may experience brief service interruptions during that time.
Browse Prior Art Database

Key Recovery System

IP.com Disclosure Number: IPCOM000122981D
Original Publication Date: 1998-Mar-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 1 page(s) / 35K

Publishing Venue

IBM

Related People

Satoh, A: AUTHOR [+2]

Abstract

Disclosed is a key-recovery scheme. The invented scheme shown in Fig.1 uses multiple-key public-key cryptosystem to generate key-recovery information. If an RSA cryptosystem on modulus n (=p*q) is assumed, three keys (APX, APY and ASE) satisfying the following equation. APX x APY x ASE = 1 mod (p-1)(q-1) are used to recover Alice's session key ACO. APX and APY are encrypted by public keys (XPU and YPU) of key-recovery agents X and Y respectively, and the session key ACO is encrypted by ASE. In order to recover ACO, the agents X and Y are requested to decrypt APX and APY from the key-recovery information by using their private-keys XSE and YSE. When APX and APY are obtained, ACO is calculated from the information (ACO/ASE/ mod n) by the following equation. (ACO/ASE/)/(APX x APY)/ = ACO/(ASE x APX x APY)/ = ACO mod n

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Key Recovery System

      Disclosed is a key-recovery scheme.  The invented scheme shown
in Fig.1 uses multiple-key public-key cryptosystem to generate
key-recovery information.  If an RSA cryptosystem on modulus n (=p*q)
is assumed, three keys (APX, APY and ASE) satisfying the following
equation.
  APX x APY x ASE = 1 mod (p-1)(q-1)
  are used to recover Alice's session key ACO.  APX and APY are
encrypted by public keys (XPU and YPU) of key-recovery agents X and Y
respectively, and the session key ACO is encrypted by ASE.  In order
to recover ACO, the agents X and Y are requested to decrypt APX and
APY from the key-recovery information by using their private-keys XSE
and YSE.  When APX and APY are obtained, ACO is calculated from the
information (ACO/ASE/ mod n) by the following equation.
  (ACO/ASE/)/(APX x APY)/ = ACO/(ASE x APX x APY)/ = ACO mod n

      The case of two recovery agents is described above.  If more
than two are required, the present scheme is easily expanded to m
agents by generating m recovering keys for agents and one private-key
satisfying the following equation.
  AP1 x AP2 x ...x APm x ASE = 1 mod (p-1)(q-1)