Sig Freund CSC 8320 Fall 2008 [email protected] Evolution of Modern Operating Systems •Centralized operating system +network access and resource sharing •Network operating system +transparency •Distributed operating system Distributed Operating System Integrating system components and resources into what appears to the user as a single local system Goal of Transparency Hide all irrelevant system-dependent details from the user and system programmer and create the illusion of a simple and easy to use system Make system simple and effective Conflicting goals requires trade-offs Access Transparency Location Transparency Migration Transparency Concurrency Transparency Replication Transparency Parallelism Transparency Failure Transparency Performance Transparency Size Transparency Revision Transparency System Goals – Efficiency Concurrency Parallelism Performance System Goals – Flexibility Access Location Migration Size Revision System Goals – Consistency Access Replication Performance System Goals – Robustness Failure Replication Size Revision Interaction and Control Transparency Communication Synchronization Distributed algorithms Performance Transparency Process scheduling Deadlock handling Load balancing Resource Transparency Resource scheduling File sharing Concurrency control Failure Transparency Failure handling Configuration Redundancy   IRIS: Infrastructure for Resilient Internet Systems Based on distributed hash tables (DHTs), that will enable a new generation of large-scale distributed applications. DHTs are robust in the face of failures, attacks and unexpectedly high loads. They are scalable, achieving large system sizes without incurring undue overhead. They are self-configuring, automatically incorporating new nodes without manual intervention or oversight. They provide a simple and flexible interface and are simultaneously usable by many applications.  E1 is a distributed operating system project, based on the following concepts: • object replication • component model support • persistence      References [1]A. S. Tanenbaum, “Distributed Operating Systems”,Prentice Hall, pp.22-25. [2]R. Chow,T. Johnson, “Distributed Operating Systems & Algorithms”, Addison Weley, pp.29-32. [3]J. Wein, “Parallel & Distributed Systems” [4]B. Karp, “RPC & Transparency”,UCL Computer Science,2006    References (continued) [5] Parallel and Distributed Operating System Group, MIT http://project-iris.net/ [6] IRIS: Infrastructure for Resilient Internet Systems http://project-iris.net/ Questions?