Secured document access control using recipient lists

Details Secured document access control using recipient lists Secured document access control using recipient lists

1998-08-28

2001-02-06

Peeso, Thomas R. (Department: 2767)

Electrical computers and digital processing systems: support

System access control based on user identification by...

C713S168000, C713S169000, C713S180000, C380S028000, C380S255000, C380S258000

Reexamination Certificate

active

06185684

ABSTRACT:

BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention is related to the field of recipient lists for encrypted documents, more specifically, the method and apparatus of the present invention is related to embedding permission attributes into a recipient list listing recipients of encrypted documents.
(2) Related Art
Secured access to data including documents may be provided through use of passwords. For example, the document format referred to as the Portable Document Format (PDF) provides a mechanism whereby secure access to the data in a PDF file can be controlled through the use of passwords. This mechanism provides for two general categories of document recipients. One is an owner and the other is a user. An owner typically has one password and the user has another password. Thus, there are only two passwords associated with an encrypted document. When issued, the owner's password enables a user to gain full access and control of a document. The user password, when issued, enables the user to gain limited access to the document as defined by the owner.
There are several disadvantages to existing methods of providing secure access to a document. For example, in order for a recipient to gain access to a document, the user (or owner) password must be made available and all recipients must use the same user (or owner) password. Additionally, currently available methods only provide two levels of access, namely an owner and a user level of access. However, different identified users may need to be privileged with different levels of access to a document.
It is therefore desirable to associate permissions to recipients of a document providing them variable levels of access to the document and use of a dedicated access key providing access to the document.
BRIEF SUMMARY OF THE INVENTION
A method for providing secured access to a document embeds a permissions attribute into a recipient list. The permissions attribute identifies permissions allowing various levels of access to a predetermined document. Each recipient listed in the recipient list has a corresponding permission associated therewith. Further, the method renders the recipient list and its contents tamper-proof.
In one embodiment of the present invention, the document to be accessed is a portable document format (PDF) document residing in a PDF file. In this embodiment, the method encapsulates the recipient list into the PDF file. A PDF viewer application controls the enforcement of the permissions on each recipient listed in the recipient list in response to the recipient attempting to access the predetermined document. In the more general case, the invention may be applied to arbitrary data.


REFERENCES:
patent: 4268911 (1981-05-01), Bell
patent: 4453074 (1984-06-01), Weinstein
patent: 4613937 (1986-09-01), Batty, Jr.
patent: 4650975 (1987-03-01), Kitchener
RSA Data Security, Inc. Public-Key Cryptography Standards (PKCS) “PKCS#7: Cryptographic Message Syntax Standard”.

Affiliated with

Also associated with

Rating

Secured document access control using recipient lists does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Secured document access control using recipient lists, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Secured document access control using recipient lists will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2613093