The present invention is directed towards providing a partial
dual-encrypted stream in a conditional access overlay system. The headend
equipment includes an aligner, identifier, and remapper (AIR) device
(615) that receives a clear stream and one or two encrypted streams,
where the two encrypted streams have been encrypted by two different
encryption schemes. The AIR device (615) identifies critical packets
associated with the clear stream and subsequently allows two encrypted
streams to pass and drops the critical packets of the clear stream. A
multiplexer (640) then combines a percentage of the non-critical packets
of the clear stream and the critical packets of the two encrypted streams
to provide the partial dual-encrypted stream.