Secure communication from one encryption domain to another using a trusted module. In one embodiment, the invention includes receiving encrypted streamed content encrypted with a first key, generating a substitution key stream based on the first key and a second key, generating a transposition key stream based on the first and second keys, and simultaneously decrypting and re-encrypting the encrypted streamed content using a combination of the substitution and transposition streams to produce re-encrypted streamed content encrypted with the second key.