  This paper addresses a problem found within the construction of Service
Oriented Architecture: the adaptation of service protocols with respect to
functional redundancy and heterogeneity of global communication patterns. We
utilise the theory of Multiparty Session Types (MPST). Our approach is based
upon the notion of a multiparty session type isomorphism, utilising a novel
constructive realisation of service adapter code to establishing equivalence.
We achieve this by employing trace semantics over a collection of local types
and introducing meta abstractions over the syntax of global types. We develop a
corresponding equational theory for MPST isomorphisms. The main motivation for
this line of work is to define a type isomorphism that affords the assessment
of whether two components/services are substitutables, modulo adaptation code
given software components formalised as session types.
