A method of encoding a packetized digital television signal consistent
with certain embodiments involves encrypting a portion of the packets
containing the digital television signal according to a first encryption
algorithm; encrypting the portion of the packets containing the digital
television signal according to a second encryption algorithm; leaving a
portion of the packets containing the digital television signal
unencrypted; assigning a primary packet identifier to the unencrypted
packets; assigning a primary packet identifier to the packets encrypted
under the first encryption algorithm; and assigning a secondary packet
identifier to the packets encrypted under the second encryption
algorithm. This abstract is not to be considered limiting, since other
embodiments may deviate from the features described in this abstract.