Abstract: A method and system for protecting computer program distribution within a broadcast medium involves encrypting at least a portion of the computer program S.sub.i using an encryption scheme keyed to both an encryption key SK.sub.i and a program identifier i. Each decryption device (PCDD) also has an associated identifier j. Two tables are generated and stored in a memory device: a first table, including correlations between the encryption key SK.sub.i and the program identifier i; and a second table, including correlations between the password key PK.sub.j and the hardware identifier j. A password P.sub.ij is generated based on both the encryption key SK.sub.i and a password key PK.sub.i is retrieved from these tables. The password P.sub.ij is transmitted to the user for subsequent use in decrypting the subject software program contained on the medium.