Group orientation: a paradigm for modern distributed systems

ABSTRACT

Increasing use of distributed systems, with the corresponding decentralization, stimulates the need for structuring activities around groups of participants, for reasons of consistency, user-friendliness, performance and dependability. Although there is a significant number of group communication protocols in the literature, they are penetrating too slowly in operating systems technology. Two important reasons are: the literal interpretation generally made of the end-to-end argument, and the lack of a layer mapping end-user needs (management of replication, competition, cooperation and group membership) into what is generally provided by the communication layer: agreement and order properties.The paper discusses both problems, proposing ways for structuring systems and defining building blocks for group-oriented activity, using concepts like object groups. It suggests that the group concept should pervade the whole architecture, from network multicasting, to group communications and management. Emerging technology will help materialize these concepts.

REFERENCES

• 1: Mustaque Ahamad and Arthur J. Bernstein. Multicast communication in Unix 4.2bsd. In The 5th Intern. Confer. on Distributed Comp. Systems, IEEE, Denver, USA, May 1985.
• 2: P. Antunes, N. Guimarães, and R. Nunes. Extending the User Interface to the Multiuser Environment. European Conf. on CSCW, CSCW Developers Workshop, Amsterdam, Sept 91.
• 3: André Schiper , Kenneth Birman , Pat Stephenson, Lightweight causal and atomic group multicast, ACM Transactions on Computer Systems (TOCS), v.9 n.3, p.272-314, Aug. 1991 [doi>10.1145/128738.128742]
• 4: T. A. Joseph , K. P. Birman, Reliable broadcast protocols, Distributed systems, ACM Press, New York, NY, 1990 [doi>10.1145/90417.90750]
• 5: David R. Cheriton , Willy Zwaenepoel, Distributed process groups in the V Kernel, ACM Transactions on Computer Systems (TOCS), v.3 n.2, p.77-107, May 1985 [doi>10.1145/214438.214439]
• 6: Eric C. Cooper, Replicated distributed programs, Proceedings of the tenth ACM symposium on Operating systems principles, p.63-78, December 1985, Orcas Island, Washington, United States
• 7: F. Cristian, Aghili. H., R. Strong, and D. Dolev. Atomic Broadcast: From simple message diffusion to Byzantine Agreement. In Digest of Papers, The 15th International Symposium on Fault-Tolerant Computing, IEEE, Ann Arbor-USA, June 1985.
• 8: Flaviu Cristian. Agreeing on who is present and who is absent in a synchronous distributed system. In Digest of Papers, The 18th International Symposium on Fault-Tolerant Computing, IEEE, Tokyo - Japan, June 1988.
• 9: Flaviu Cristian, Robert D. Dancey, and Jon Dehn. Fault-tolerance in the advanced automation system. In Digest of Papers, The 20th International Symposium on Fault-Tolerant Computing, IEEE, Newcastle-UK, June 1990.
• 10: H. Garcia-Molina and Annemarie Spauster. Message ordering in a multicast environment. In 9th Internacional Conference on Distributed Computing Systems, pages 354-361, IEEE, June 1989.
• 11: J. A. Marques , P. Guedes, Extending the operating system to support an object-oriented environment, Conference proceedings on Object-oriented programming systems, languages and applications, p.113-122, October 02-06, 1989, New Orleans, Louisiana, United States
• 12: The ANSA Reference Manual. Architecture Projects Management, Ltd, Cambridge, UK, release 1.1 edition, July 1989.
• 13: Larry Hughes, A multicast interface for UNIX 4.3, Software—Practice & Experience, v.18 n.1, p.15-27, Jan., 1988 [doi>10.1002/spe.4380180104]
• 14: H. Kopetz, G. Grunsteidl, and J. Reisinger. Fault-tolerant membership service in a synchronous distributed real-time system. In IFIP WG10.4 Int. Working Conference on Dependable Computing for Critical Applications, Sta Barbara - USA, August 1989.
• 15: Hermann Kopetz , Andreas Damm , Christian Koza , Marco Mulazzani , Wolfgang Schwabl , Christoph Senft , Ralph Zainlinger, Distributed Fault-Tolerant Real-Time Systems: The Mars Approach, IEEE Micro, v.9 n.1, p.25-40, January 1989 [doi>10.1109/40.16792]
• 16: R. Ladin. B. Liskov, and L. Shrira. Lazy replication: exploiting the semantics of distributed services. In Workshop on the Management of Replicated Data, pages 31-34, IEEE, Houston - USA, November 1990.
• 17: Leslie Lamport , Robert Shostak , Marshall Pease, The Byzantine Generals Problem, ACM Transactions on Programming Languages and Systems (TOPLAS), v.4 n.3, p.382-401, July 1982 [doi>10.1145/357172.357176]
• 18: G. Le Lann. An analysis of different approaches to distributed computing. In Proc 1st International Conference on Distributed Computing Systems, IEEE, Alabama-USA, 1979.
• 19: Shivakant Mishra, Larry L. Peterson, and Richard D. Schlichting. A membership protocol based on partial order. In 2nd Intl. Working Conf. on Dependable Computing for Critical Applications, pages 1-18, IFIP WG10.4, USA, February 1991.
• 20: Larry L. Peterson , Nick C. Buchholz , Richard D. Schlichting, Preserving and using context information in interprocess communication, ACM Transactions on Computer Systems (TOCS), v.7 n.3, p.217-246, Aug. 1989 [doi>10.1145/65000.65001]
• 21: D. Powell , I. Bey , J. Leuridan, Delta Four: A Generic Architecture for Dependable Distributed Computing, Springer-Verlag New York, Inc., Secaucus, NJ, 1991
• 22: J. H. Saltzer , D. P. Reed , D. D. Clark, End-to-end arguments in system design, ACM Transactions on Computer Systems (TOCS), v.2 n.4, p.277-288, Nov. 1984 [doi>10.1145/357401.357402]
• 23: P. Veríssimo and José A. Marques. Reliable broadcast for fault-tolerance on local computer networks. In Ninth Symposium on Reliable Distributed Systems, IEEE, Huntsville, Alabama-USA, October 1990. Also as INESC AR/24-90.
• 24: Paulo Verissimo, Peter Barrett, Peter Bond, Andrew Hilborne, Luis Rodrigues, Douglas Seaton. The Extra Performance Architecture (XPA). In D. Powell, editor, Delta- 4 - A Generic Architecture for Dependable Distributed Computing. Springer Verlag, November 1991.
• 25: Paulo Veríssimo. Real-time Data Management with Clockless Reliable sBroadcast Protocols. In Workshop on the Management of Replicated Data, IEEE, Houston, Texas-USA, November 1990. also as INESC AR/25-90.
• 26: Werner Vogels and Paulo Veríssimo. Supporting process groups in internetworks with lightweight reliable multicast protocols. In ERCIM Workshop on Distributed Systems, Lisboa, Portugal, November 1991.