Defense-in Depth security defines a set of graduated security tasks, each of which performs a task that must complete before another task can complete. Only when these tasks complete successfully and in the order prescribed by Defense-in-Depth security criteria is a final process allowed to execute. Through such Defense-in-Depth security measures, vulnerable software, such as bytecode, can be verified as unaltered and executed in a secure environment that prohibits unsecured access to the underlying code.