Patent ID: 7349538
Filing Date: 2008-03-25
Classification: H04L

Abstract:
1. A method of generating a private key for a recipient z in a system, wherein the recipient z is n+1 levels below a root PKG in the hierarchy, and wherein the recipient is associated with a recipient ID-tuple (ID z1 , . . . , ID z(n+1 ) that includes identity information ID z)n+1) associated with the recipient and identity information ID zi associated with each of n lower-level PKGs in the hierarchy between the root PKG and the recipient, the method comprising: generating a first cyclic group G selecting a function ê capable of generating an element of the second cyclic group G selecting a root generator P selecting a random root key generation secret s generating a root key generation parameter Q generating a public element P generating a lower-level secret element S generating a lower-level key generation parameter Q generating a recipient public element P generating a recipient private key associated with the recipient.