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Security Issues in P2P Systems

Prof. Ravi SandhuLaboratory for Information Security Technology

George Mason University

www.list.gmu.edu

sandhu@gmu.edu

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Mainframe → Client-Server → P2P

• Mainframe era:• 1970’s• Dumb terminals connected to a big mainframe • Mainframes possibly networked together

• Client-server:• Late 1980’s• Many clients, 1 user per client• Dedicated servers• Single client can access multiple servers• Significant computing resources on client

• Peer-to-Peer (P2P)• Late 1990’s• Each computer is a client and a server• Takes on whatever role is appropriate for a given task at a given time• Harnesses computing and communication power of the entire network

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P2P versus Client-Server: Idealized View

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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No Clear Border

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Hybrid P2P Systems

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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P2P Perspective

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Napster

From THE FUTURE OF PEER-TO-PEER COMPUTING, Loo, CACM Sept 2003

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Power Server

From THE FUTURE OF PEER-TO-PEER COMPUTING, Loo, CACM Sept 2003

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Power Server Coordinator

From THE FUTURE OF PEER-TO-PEER COMPUTING, Loo, CACM Sept 2003

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Comparison of Different P2P Models

From THE FUTURE OF PEER-TO-PEER COMPUTING, Loo, CACM Sept 2003

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Taxonomy of Computer Systems

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Taxonomy of P2P Systems

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Classification of P2P Systems

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Taxonomy of P2P Applications

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Taxonomy of P2P Markets

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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P2P Markets versus P2P Applications

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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P2P System Architecture

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Security Issues in P2P Systems

• Many old issues carry over

• New issues emerge

• Old issues are re-emphasized

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Security

• Protection against malicious downloaded P2P application code

• Enabling technologies• Java sandboxing• Trusted computing

From THE FUTURE OF PEER-TO-PEER COMPUTING, Loo, CACM Sept 2003

Old issue re-emphasized

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Security (claimed to be new issues)

• Multi-key encryption• Annonymity requirement for Publius

• Sandboxing

• Digital Rights Management

• Reputation and Accountability

• Firewall Traversal and Hidden Peers

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Annonymity (is this a security issue?)

From Peer-to-Peer Computing, Milojicic et al, HP Laboratories, HPL-2002-57, March 8th, 2002

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Security in Data Sharing Systems• Availability

• DOS attack, e.g., chosen-victim attack– Use “amplification” mechanism of P2P system

• File availability• File authenticity

• How do I know this is the file I am looking for?• Anonymity

• Lots of work in this area• Need anonymity at all layers of the network stack

• Access Control• DRM• Usage Control

From Open Problems in Data-Sharing Peer-to-PeerSystems, Neil Daswani, Hector Garcia-Molina, and Beverly Yang, LNCS 2572, pp. 1–15, 2003.

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Security in Data Sharing Systems(P2P Overlay Networks)

• Routing• Secure nodeId assignment• Robust routing primitives• Ejecting misbehaving nodes

• Storage• Quota architectures• Distributed auditing• Other forms of fairness

• Trust

From A Survey of Peer-to-Peer Security Issues, Dan S.Wallach, LNCS 2609, pp. 42–57, 2003..