1. A demand paging system comprising a dynamic random access memory (DRAM); a microprocessor for executing a protected application having a secure internal memory having a physical address space and coupled to said DRAM; and a non-volatile memory storing a coded physical representation of operations accessible by said microprocessor and including a coded physical representation of operations to establish a data structure pertaining at least in part to both the secure internal memory and the DRAM, the data structure organizing the protected application in the secure internal memory into virtual pages by a first index for a book keeping element in use, and a second index for a block book keeping block in use, and operations to demand page between the secure internal memory and the DRAM utilizing the data structure; wherein the coded physical representation of operations includes a representation of operations to access the data structure by a third index for different virtual machine contexts.