RELIABLE COMMUNICATION IN VPL

                      Eva Kühn and Franz Puntigam
    University of Technology Vienna, Institute of Computer Languages
           Argentinierstr. 8, A-1040 Vienna, Austria, Europe
                 {eva,franz}@mips.complang.tuwien.ac.at

We compare different degrees of architecture abstraction and communication
reliability in distributed programming languages. A nearly architecture 
independent logic programming language and system with reliable communication, 
called VPL (Vienna Parallel Logic) is presented. We point out the
contradiction between complete architecture independence and reliable
high-level communication in programming languages. The description of an
implementation technique of VPL's reliable communication on shared memory and 
distributed architectures comprises a major part of this paper. The 
reliable communication is based on the specification of consistent system
states that must survive system failures.

Keywords: parallel programming paradigms, parallel language extensions,
          implementation of parallel languages.