Ten15: an abstract machine for portable environments

Abstract

Ten15 is an abstract machine which is defined algebraically with strong typing enforced throughout. The structure and operations of this machine are sufficiently rich to allow the efficient implementation of a general purpose program-support environment extending over networks. Since Ten15 is an abstraction of programming languages rather than hardware, it also serves as a target in the compilation of standard languages. As well as giving common addressing mechanisms, Ten15 provides a common system of types which is enforced throughout the system whether in user's programs, system utilities or any other tools, alleviating many of the interfacing difficulties encountered when independently written programs try to interact. Porting an environment based on Ten15 to a new machine consists of writing a translator of Ten15 programs for the new machine together with a relatively small part of the system kernel mainly concerned with peripheral drivers; a normal bootstrap gives the ported environment. The resulting environment is one in which the type system ensures the integrity of any data or program in it and is used as the basis to give both security and privacy. In addition the algebraic nature of the machine helps one to do formal reasoning about programs running in it.