Secure Operating Systems

When used in the context of computer systems, and in particular computer operating systems, the word "security" can have (at least) three quite different meanings.

It can mean that the operating system code has been proven "correct" in the quasi mathematical sense that a specification exists and that the code of the operating system has been proven to conform to the specification. This is the sense in which the word "secure" is sometimes used in association with the claim that Sel4 ( is the "world's most highly assured OS kernel". This is not the meaning of "secure" when we describe SPEEDOS as secure.

Similarly the reliance on encryption techniques to guarantee security is not the sense in which the word security is used here, although SPEEDOS actually uses such techniques for transferring information over the Internet and for accessing discs.

On this website and in documents downloadable from it the word security is used at the architectural level, i.e. with respect to the hardware instruction set design and the operating system design (especially but not exclusively the design of the kernel). As will become evident, the SPEEDOS architecture is radically different from that of conventional systems.