Patent ID: 7796760
Filing Date: 2010-09-14
Classification: H04L

Abstract:
1. A computer-implemented method for sending a message from a sending client to a recipient client, the computer-implemented method comprising: receiving, at the sending client from a policy server, a user key that is generated based upon a user key descriptor that includes user identification data that uniquely identifies a user associated with the sending client, receiving, at the sending client, a user recovery key that is generated based upon both a server recovery key and the user identification data, wherein the policy server generates the server recovery key and manages the server recovery key in accordance with an encryption key management policy; generating, at the sending client, an encrypted message by encrypting the message with a message key; generating, at the sending client, an encrypted message key by encrypting the message key with at least the user key and the user recovery key; generating, at the sending client, metadata that defines one or more attributes of the message; generating, at the sending client, signature data and encrypting the metadata with the user key; and sending, from the sending client to the recipient client, the encrypted message, the encrypted message key, the metadata and the signature data.