Abstract: A system and method of deauthorizing a computer-based licensed product. During the deauthorization process, an end user device transmits an encrypted character string (i.e., the Proof Of Removal Code), including a Transaction ID, to a licensing authority. The licensing authority receives the Proof Of Removal Code from the end user device and decrypts the Transaction ID using a decryption key associated with a product for which the end user is seeking deauthorization. The licensing authority compares Transaction IDs and produces a Deauthorization number, which is sent to the end user device. Each product is associated with a different decryption key resulting in a different Deauthorization number being produced for each product based on the same Transaction ID. Thus, the same identical Transaction ID can be decrypted into as many different Deauthorization numbers as there are products.

Abstract: A system and method of deauthorizing a computer-based licensed product. During the deauthorization process, an end user device transmits an encrypted character string (i.e., the Proof Of Removal Code), including a Transaction ID, to a licensing authority. The licensing authority receives the Proof Of Removal Code from the end user device and decrypts the Transaction ID using a decryption key associated with a product for which the end user is seeking deauthorization. The licensing authority compares Transaction IDs and produces a Deauthorization number, which is sent to the end user device. Each product is associated with a different decryption key resulting in a different Deauthorization number being produced for each product based on the same Transaction ID. Thus, the same identical Transaction ID can be decrypted into as many different Deauthorization numbers as there are products.

Abstract: Systems and methods use features of an inode's or file identifier's (id) assignment, uniqueness and randomness, to fingerprint an end user device or system for authorization of a license. During the installation process of an operating system on an end user device certain directories and files created, that remain in place for the life of the installation, result in inodes or file ids that will be largely random as they depend, for example, on which files are installed and in what order their installation takes place. Since a modern operating system will have several processes occurring in parallel during installation the order in which files are installed will vary more or less randomly from system to system. To fingerprint the system a group of files that is fixed during the operating systems lifetime, such as system directories, are used to determine the inodes associated with these directories as represented by their inode number.

Abstract: A system and method of authorizing a product including transmitting from an end user device a character string, including a Transaction ID, to a licensing authority. The licensing authority encrypts the Transaction ID using an encryption key associated with a product for which the end user is seeking authorization to produce an Authorization number. Each product is associated with a different encryption key resulting in a different Authorization number being produced for each product based on the same Transaction ID. The licensing authority then returns the Authorization number to the end user device. A decryption processor associated with the end user device decrypts the Authorization number using an unchangeable decryption key and compares the decrypted Authorization number with the Transaction ID. If the decrypted Authorization number matches the Transaction ID the product is authorized.