Communication primitives for ubiquitous systems or RPC considered harmful

Abstract

RPC is widely used to access and modify remote state. Its procedural call semantics are argued as an efficient unifying paradigm for both local and remote access. Our experience with ubiquitous device control systems has shown otherwise. RPC semantics of a synchronous, blocking invocation on a statically typed interface are overly restrictive, inflexible, and fail to provide an efficient unifying abstraction for accessing and modifying state in ubiquitous systems. This paper considers other alternatives and proposes the use of comvets (conditional, mobility aware events) as the unifying generic communication paradigm for such systems.