Process control migration towards LHC ventilation functionality

The adaptation of the ventilation systems as well as the integration of equipment to fit with the new LHC ventilation requirements lead us to consider a global re-engineering of the existing control system. This, decade old process control structure is composed of elements which are mixed between industrial and home made devices. The proposed modifications are made in order to upgrade the present control system and to provide efficient and well adapted control architecture to integrate the LHC ventilation equipment of the injection tunnels. Moreover, we need a plan for the next fifteen years of the LHC life cycle. The document is to present the situation of the present control system of the LEP ventilation process and to propose a plan for the migration of the control architecture. This is done considering the fact that elements of the present control infrastructure could no longer be supported from 2003 and major components must be removed from the CERN communication infrastructure