PUBLIC KEY CIPHERING SYSTEM ADOPTING ROBUST AND RECOVERABLE DISTRIBUTED THRESHOLD LEVEL SECURITY COMMON SHARE SYSTEM WITH FORWARD DIRECTIVE PROPERTY

摘要

PROBLEM TO BE SOLVED: To obtain a public key ciphering system adopting a robust and recoverable distributed threshold level security common share system with forward directive property by keeping at least (k+1) servers among n-sets of servers active and correct. ;SOLUTION: A server linked by a communication network is initialized to generate a key (310) and the operation of each server is synchronized with another finished round (312). In order to generate an updated key, the sets of random number defining each polynomial of the server at the end of the other round are extracted, a message derived from the polynomial is multiple address communicated by a communication network to update the key (314). A key updated to generate compromised server sets is checked and when any error is in existence, the key is set again (316), each low-order bit common share of the servers is calculated, an extracted message is multiple address communicated by the communication network and then recovered (318).;COPYRIGHT: (C)1997,JPO