System for computer software protection

A system for restricting the execution of a computer program comprising:

• means for re-enciphering a computer program from a first cipher form stored on a distribution media to a second cipher form during initial installation of said program onto predetermined storage means of a file server wherein said second cipher form is executable only on authorized computer systems attached to said server;
• means for loading said program from said file server onto the authorized computer systems;
• and
• means for executing said program on the authorized computer systems.

A method for restricting the execution of a computer program comprising the steps of:

• enciphering a computer program in a first cipher form stored on a distribution media;
• initially installing said program in a computer system having a crypto microprocessor by perfoming the steps of:
• obtaining data from a remote exchange system;
• re-enciphering said program from said first cipher form to a second cipher form by translating said program with said crypto microprocessor an said data;
• and
• storing said program onto storage a predetermined means of the computer system in said second form;
• and
• transferring said program from the predetermined storage means to the computer system, deciphering said program from said second cipher form to a deciphered form with said crypto microprocessor, and executing said program in said deciphered form.