Laura: a coordination language for open distributed systems

Open distributed systems are an emerging class of distributed systems that have to take into account a number of heterogeneities in the system components and possibly high dynamics in the system structure by unrestrictedly joining and leaving agents. Uncoupled processing is a basis for a solution of the coordination problem that arises. Laura is a coordination language for open distributed systems following this paradigm by introducing a service space via which agents offer and request services without knowing about each other. They place and withdraw forms from the service space describing the type of service offered or requested. Type conformance based on subtyping determines if the forms match. An initial Laura implementation is described and further issues such as scalability and a role model are considered