MOCCA - towards a distributed CCA framework for metacomputing

We describe the design and implementation of MOCCA, a distributed CCA framework implemented using the H2O metacomputing system. Motivated by the quest for appropriate metasystem programming models for large scale scientific applications, MOCCA combines the advantages of component orientation with the flexible and reconfigurable H2O middleware. By exploiting unique capabilities in H2O, including client-provider separation, security, and negotiable transport protocols, enhancements to both functionality and performance could be attained. The design and implementation of MOCCA highlights the natural match between CCA components and H2O pluglets, both in structure and invocation methodology. An outline of how native CCA modules can be supported in the MOCCA framework describes the potential for future deployment of legacy codes on metacomputing systems. We also report on preliminary experiences with test applications and sample performance measurements that favorably compare MOCCA to alternative component frameworks for tightly- and loosely-coupled metacomputing systems.