Cryptographic Sequences with Linear Cellular Automata

Hi, I need help to make an application of cryptography. I had trouble in some parts. nearly 70 percent of this application is almost done, so if you are interested I hope you can do something like the following. 1. Secret-key cryptography divided into block and stream ciphers. As opposed to block ci-phers, stream ciphers encrypt each data symbol (as small as a bit) into a ciphertext symbol under a time-varying transformation. 2. LFSR controlled by another LFSR (which may be the same one). 3. Cellular Automata (CA) will be used for solutions of linear diference equations with constant coecients. If you understand and experts, we can talk about things that I need on a private message. Thank you Sincerely. Flynn