Browse Prior Art Database

Time restrictions on files. Disclosure Number: IPCOM000016246D
Original Publication Date: 2002-Oct-05
Included in the Prior Art Database: 2003-Jun-21
Document File: 3 page(s) / 81K

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Disclosed is a method to avoid unauthorized access to a computer file before a given date.

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Time restrictions on files.

Disclosed is a method to avoid unauthorized access to a computer file before a given date.

There are situations where the information (1) related to a particular "fact" should not be communicated to the "world" before a fixed (or given) date. For example, businesses results, company reorganization, and employee's movement are sensitive information regarding the company life, which are "confidential" until a given date. Some times those information have to be physically delivered early although they should be spread out only after the specified date. There are also other cases. When a public bureau (or a state-owned company) has to purchase some goods it asks to their supplier to make an offer. The public bureau stores all the offers without opening them (it's a must) until the day fixed for the contract assignment. The method provided here solves the problem of delivering a document before the contents can be read.

  There are three actors: Token. It's a special file basically composed of two parts: the UUID (Universal Unique ID) that identifies it univocally and a key used to encrypt the file. The key represents the public portion of an asymmetric key.

Asymmetric or public-key cryptography differs from conventional cryptography because the key material is divided into two components:
1. A private key, to which only the user has access, and
2. A public key, which may be published or distributed on request. Each key generates a function used to transform text. The private key generates a private transformation function, and the public key generates a public transformation function. The functions are inversely related, i.e., if one function is used to encrypt a message, the other is used to decrypt the message. The order in which the transformation functions are invoked is irrelevant. Note that since the key materi...