Patent ID: 8391481

Claim:
A method comprising: receiving a new management key in a device having a security class level, in an ordered hierarchy of levels, said device being in a cluster of devices including devices having a plurality of security classes; calculating a new binding key for said security class based on said new management key and other values; rebinding a bound title key encrypted with a previously used binding key, said bound title key having a security class designated by the security class of said previously used binding key; if said device security class is lower than the security class of said bound title key, doubly binding said bound title key by encrypting with said new management key, and saving said doubly bound title key; and if said device security class is not lower than the security class of said bound title key, rebinding said bound title key by decrypting with said old binding key for the security class of said bound key, and encrypting with said new binding key for the security class of said bound title key.