Abstract: A method of processing encrypted communications sent by a first party, the method including the steps of: receiving from the first party a message that has a first part, a second part, a third part and a fourth part, wherein the first part includes a first block of information that is encrypted by using a key k1, the second part includes a second block of information that is encrypted by using a key k2, the third part includes a third block of information that is encrypted by using a key R, and the fourth part includes a fourth block of information that is encrypted by using the key R, wherein the third block of information includes k1 and the fourth block of information includes k2; blinding the fourth part; sending the third part and the blinded fourth part to a recryptor; receiving from the recryptor the k1 key re-encrypted by using a first key; and receiving from the recryptor a fifth block of information which is the blinded fourth block of information that has been encrypted by using a second key.
Type:
Grant
Filed:
April 9, 1997
Date of Patent:
June 9, 1998
Assignee:
Microsoft Corporation
Inventors:
Jeffrey F. Spelman, Matthew W. Thomlinson