公开(公告)号：DE60233929D1

公开(公告)日：2009-11-19

申请号：DE60233929

申请日：2002-01-23

Applicant: IBM

Inventor： LOTSPIECH JEFFREY BRUCE ,  NAOR DALIT ,  NAOR SIMEON

IPC: H04L9/08 ,  H04L12/18 ,  H04L29/06

Abstract: A tree is used to partition stateless receivers in a broadcast content encryption system into subsets. Two different methods of partitioning are disclosed. When a set of revoked receivers is identified, the revoked receivers define a relatively small cover of the non-revoked receivers by disjoint subsets. Subset keys associated with the subsets are then used to encrypt a session key that in turn is used to encrypt the broadcast content. Only non-revoked receivers can decrypt the session key and, hence, the content.

公开(公告)号：AT445269T

公开(公告)日：2009-10-15

申请号：AT02710108

申请日：2002-01-23

Applicant: IBM

Inventor： LOTSPIECH JEFFREY ,  NAOR DALIT ,  NAOR SIMEON

IPC: H04L9/08 ,  H04L12/18 ,  H04L29/06

Abstract: A tree is used to partition stateless receivers in a broadcast content encryption system into subsets. Two different methods of partitioning are disclosed. When a set of revoked receivers is identified, the revoked receivers define a relatively small cover of the non-revoked receivers by disjoint subsets. Subset keys associated with the subsets are then used to encrypt a session key that in turn is used to encrypt the broadcast content. Only non-revoked receivers can decrypt the session key and, hence, the content.