Secure Location-Independent
Autonomic Storage Architectures
GR/S44501/01
February 2004 - October 2007
Graham Kirby, Alan Dearle, Stuart Norcross,
Ron Morrison, Markus Tauber & Rob MacInnis
School of Computer Science, University of St Andrews
{graham, al, stuart, ron, markus, rob}@cs.st-andrews.ac.uk
Overview
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Goal: ubiquitous distributed storage infrastructure
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ease of use
operate on non-trusted platform
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flexibility allowing trade-off among:
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resilience of data
performance
capacity
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Research Progress
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Core storage infrastructure
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Byzantine tolerance
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withstands benign or malicious failure of participating nodes
Autonomic management
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scalable, location-independent data storage and retrieval
maintains data replication, caching & placement
Spin-offs
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generic autonomic manager
P2P application toolkit
flexible middleware
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Related Work
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Research projects
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OceanStore
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Ivy
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concurrent updates can yield inconsistent views
overhead increases with number of writers
PAST
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relatively fixed ‘inner ring’
primary-based Byzantine protocol
no update
...
Commercial
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Apple iDisk, Amazon S3
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remote storage model
designed for server farm where Byzantine tolerance not an issue
...
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System Requirements
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Desired properties
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scalability through decentralisation
self-configuration
resilience through replication
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automatic maintenance of replicated data
consistent global view in face of concurrent update
Storage model
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System Architecture
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Autonomic Management
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P2P layer
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scheduling of self-repair operations
Storage layer
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resilience
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maintenance of replicas
degree of replication
distribution of replicas
performance
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consistency/responsiveness trade-off
client side caching
predictive placement
data block size
encoding
garbage collection
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Conclusions
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Research contributions
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Promising prototype
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much work still to do on autonomic management
Funding applications
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scalable, location-independent data storage infrastructure
Byzantine tolerant services on un-trusted P2P network
symmetric Byzantine update serialisation algorithm
P2P application toolkit
policy-free middleware
further develop this approach
apply to P2P-based distributed object model
generalise P2P application toolkit
platform for π-calculus based open services
Project details: http://asa.cs.st-andrews.ac.uk/
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Publications
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Generating a Family of Byzantine Tolerant Protocol Implementations Using a
Meta-Model Architecture. Submitted to: DSN 2007 Workshop on Architecting
Dependable Systems. 2007.
Hosting Byzantine Fault Tolerant Services on a Chord Ring. Submitted to: DSN
2007 Workshop on Architecting Dependable Systems. 2007.
A Peer-to-Peer Middleware Framework for Resilient Persistent Programming.
University of St Andrews Report CS/06/1. 2006.
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A Methodology for Developing and Deploying Distributed Applications. In: Proc.
3rd International Working Conference on Component Deployment (CD2005),
Grenoble, France, pp 37-51. 2005.
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A Peer-To-Peer Infrastructure for Resilient Web Services. IEEE International
Workshop on Advanced Architectures and Algorithms for Internet Delivery and
Applications (AAA-IDEA 2005).
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RAFDA: Middleware Supporting the Separation of Application Logic from
Distribution Policy. University of St Andrews Report CS/05/3. 2005.
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Promoting Component Reuse by Separating Transmission Policy from
Implementation. University of St Andrews Report CS/05/1. 2005.
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