Improving protection of PHP source code using cryptology models

Nowadays there is growing issue in protecting PHP scripts from unwanted using, copying and modifications. Existing solutions on source code level are mostly working as obfuscators, are free, and are not providing any serious protection. Solutions that encode opcode are more secure but are commercial and require closed-source proprietary PHP interpreter's extension. Additionally, encoded opcode is not compatible with future versions of interpreters which imply rebuying encoders from authors. Finally, if extension source-code is compromised, all script encoded by that solution are compromised too. In this paper we present a novel model for free and open-source PHP script protection solution. Protection level provided by proposed solution is equal to protection level of commercial solutions. Model is based on conclusions from using standard cryptology models for analyzing strengths and weaknesses of existing solutions when scripts protection is seen as secure communication channel in cryptology.