Distributed Viewpoint Equivalences for Higher Order Processes

In this paper, we give two distributed viewpoint equivalences for higher order pi-calculus. We show that the two equivalences are equivalent. Furthermore, we prove that distributed viewpoint equivalences are finer than context bisimulation and are coarser than higher order bisimulation. For some sub languages of higher order pi-calculus, we show that these distributed viewpoint equivalences coincide with higher order bisimulation or context bisimulation.