This paper studies one important aspect of distributed systems, locality, using a calculus of distributed higher-order processes in which not only basic values or channels, but also parameterised processes are transferred across distinct locations. An integration of the subtyping of #lambda# -calculus and IO-subtyping of the #pi# -calculus offers a tractable tool to control the locality of channel names in the presence of distributed higher order processes. Using a local restriction on channel capabilities together with a subtyping relation, locality is preserved during reductions even if we allow new receptors to be dynamically created by instantiation of arbitrary higher-order values and processes. We also show that our method is aapplicable to more general constraints, based on local and global channel capabilities.
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