Retrofitting and developing applications for a trusted computing base

The authors discuss the concept of a software analysis procedure to aid in the conversion of existing applications and in the development of applications for use with a trusted computing base (TCB). In this procedure, the system processes are broken down into small entities that permit detailed analysis to ensure that the trusted processes will be at the absolute minimum. The use of this analysis within two separate projects, one involving conversion of existing software and one involving development of software, is discussed to demonstrate the process. It is concluded that the processes identified and needing to be trusted were those which violated the security model; all other security-related processes are supplied by the TCB. It is further concluded that performance problems caused by TCB mediation brought about by security requirements can be somewhat alleviated by implementing larger object-level entities in a layered fashion