  For the last two decades, software architecture has been adopted as one of
the main viable solutions to address the ever-increasing demands in the design
and development of software systems. Nevertheless, the rapidly growing
utilization of communication networks and interconnections among software
systems have introduced some critical challenges, which need to be handled in
order to fully unleash the potential of these systems. In this respect,
Ultra-Large-Scale (ULS) systems, generally considered as a system of systems,
have gained considerable attention, since their scale is incomparable to the
traditional systems. The scale of ULS systems makes drastic changes in various
aspects of system development. As a result, it requires that we broaden our
understanding of software architectures and the ways we structure them. In this
paper, we investigate the lack of an architectural maturity model framework for
ULS system interoperability, and propose an architectural maturity model
framework to improve ULS system interoperability.
