Patent ID: 9716693
Date: 2017-07-25
CPC Classifications: G06F,H04L

Claim:
1. A digital rights management method implemented in a system including a client computer and a digital rights management server (RMS server) for protecting electronic mails (emails), comprising: by the client computer: (a) receiving encrypted data representing an email, the email including a message and one or more attachments, the data having been encrypted by an email application of the client computer based on an original digital rights management (DRM) policy selected by a user; (b) obtaining from the user one or more DRM policies to be applied to the attachments of the email, each attachment corresponding to one specified DRM policy; and (c) transmitting the encrypted data representing the email, along with data specifying the DRM policy to be applied to each attachment and data specifying the original DRM policy, to the RMS server; by the RMS server: (d) receiving, from the client computer, the encrypted data representing the email, along with the data specifying the DRM policy to be applied to each attachment and the data specifying the original DRM policy; (e) decrypting the encrypted data representing the email, including the message and the one or more attachments, which has been received from the client computer in step (d); (f) applying digital rights management protection to each attachment which has been decrypted in step (e), based on the specified DRM policy for the attachment as specified in the data received from the client computer in step (d), to generate a protected document for each attachment; (g) re-composing an email document which includes as attachments the protected documents generated in step (f) to generate a re-composed email document; (h) applying digital rights management protection to the re-composed email document generated by step (g) based on the original DRM policy received from the client computer in step (d); and (i) transmitting the re-composed email document to an email exchange server.