The Architecture of the Starfish System: Mapping the Survivability Space Kim Kihlstrom Chris Phillips Chris Ritchey Ben LaBarbera Westmont College Priya Narasimhan Carnegie Mellon University

The Starfish SystemIASTED PDCS 2003 Starfish Goals Provide survivability for middleware applications Not specific to any middleware system Applicable to local and wide area systems Provide support for connected enterprises such as web services Allow linking of multiple Starfish

The Starfish SystemIASTED PDCS 2003 Starfish Protocol Stack

The Starfish SystemIASTED PDCS 2003 Creating the Survivability Space Define what is meant by survivability Evaluate existing systems Identify tradeoffs in survivability issues Develop cohesive framework for survivable system design

The Starfish SystemIASTED PDCS 2003 Survivability Encompasses but goes beyond reliability and security Provide useful services even in event of malicious attacks, intrusions, accidents, or faults

The Starfish SystemIASTED PDCS 2003 Survivability Space

The Starfish SystemIASTED PDCS 2003 Reliability Subspace

The Starfish SystemIASTED PDCS 2003 Security Subspace

The Starfish SystemIASTED PDCS 2003 Quality of Service Subspace

The Starfish SystemIASTED PDCS 2003 Mapping of Prior Systems Mapped a number of existing systems to survivability space

The Starfish SystemIASTED PDCS 2003 Starfish Philosophy Starfish allows for tradeoffs between security, reliability, and quality of service by providing body, shoulders, and arm regions Body: Byzantine fault model and high security guarantees, but lower performance and not scalable to wide area or large number of processors Arms: High performance and highly scalable, but supports only crash/omission/timing fault model and less stringent security guarantees Shoulders: Intermediate fault tolerance, security, performance and scalability

The Starfish SystemIASTED PDCS 2003

The Starfish SystemIASTED PDCS 2003 Linked Starfish

The Starfish SystemIASTED PDCS 2003 Starfish Reliability Subspace

The Starfish SystemIASTED PDCS 2003 Starfish Security Subspace

The Starfish SystemIASTED PDCS 2003 Starfish Quality of Service Subspace

The Starfish SystemIASTED PDCS 2003 Reliability Mechanisms Active and passive replication Majority voting Secure reliable ordered multicast Byzantine fault detector Value fault detector Secure membership Vaccination Timeouts Retransmission

The Starfish SystemIASTED PDCS 2003 Security Mechanisms Threshold scheme Encryption Identifiers Passwords MACs Signatures Byzantine fault detector Value fault detector Secure membership Logging Anomaly detection Sandboxing Intrusion history Message digests State transfer Quarantine Vaccination Membership Message Digests Removal Recovery

The Starfish SystemIASTED PDCS 2003 Quality of Service Mechanisms Removal/addition Migration Hierarchical Groups Message prioritization Optimistic Delivery Live Upgrades

The Starfish SystemIASTED PDCS 2003 Conclusions Mapping of prior systems to survivability space Mapping of Starfish body, shoulders, and arms to survivability space Identification of survivability properties and mechanisms for Starfish body, shoulders, and arms

The Starfish SystemIASTED PDCS 2003 Questions and Feedback Kim Kihlstrom Priya Narasimhan Chris Phillips