1. BY: REBECCA NAVARRE & MICHAEL BAKER II Persea: Making Networks More Secure Since Early 2013

2. Biography Rebecca Navarre Wesleyan College Applied Mathematical Sciences Michael Baker II Tarrant County College Mechanical Engineering

3. Background Peer-to-Peer Networks Distributed Hash Tables (DHTs) Kad

4. Peer-to-Peer Networks Purpose: file & resource sharing network Nodes capable of acting like client and server Accessible to peers directly( for pure, no central/intermediary entity) Workload is partitioned between peers. There is no central point of failure. Examples: Napster(centralized), Freenet(Gnutella protocol), Gnutella2 and Kazaa (hybrid)

5. Peer-to-Peer cont. Hybrid vs. Pure  For Hybrid:  Allows for a central entity to provide network services or act as a security check.  For Pure  All nodes are equal.  When one node is removed, the network continues without suffering a loss.

6. Distributed Hash Table Purpose: System of Efficient Resource Discovery Messages come into DHTs, retrieved by matching keys Based on pairs. If change occurs, minimal disruption Allows for large scale data recovery KEYVALUE 1100 2200 3300 4400

7. Kad Purpose: offers consistent search/find protocol Figure 1

8. Kad Continued Nodes know about neighbors K-buckets offer resistance to DOS attacks Can’t flood out nodes with LIFO Lookup Source selects α # of closest nodes from its k-bucket Source sends look up request to each α node selected Each α node returns β # of nodes from searching k- buckets Source then has α into β # of nodes in list From this, source selects selects α # of closest nodes from its k-bucket Process continues until it reaches target node

9. Persea Security Initial Security  Social Network & DHT  Invitation Only  Kad  Message entry DHT Social Network New Node N

10. Hierarchical Node ID Distribution Security Bootstrap/Initiator Nodes ABC D a1 a2 q1 p2p1 d2d1 0 1 2 3 63 64 127 128 191192 255 14 15 28 7611 4 193 206 207 221 Chunk factor:.65 Chunk Factor Calculation 64^(.65) = floor(14.929) = 14

11. Persea Look Up Effeciency Replication Node holding pair k=3, stored in k-closest nodes KAD PERSEA

12. What Persea Is Up Against? Sybil Attack Advanced Attack  Node Insertion  Node ID Hijacking

13. The Roles of the Attackers Silent Active

14. Topologies SOCIAL NETWORKNODESEDGES Wiki-Vote7115103689 Soc-Epinions175879508837

15. Silent vs. Active Sybil Attack Social Network Data Set used: soc-Epinions1

16. Hop Count: Active Sybil Attack

17. Active Sybil Attack(wiki-Vote) Social Network Data Set used: wiki-Vote

18. Advanced & Sybil Attack

19. Nodes per Attack Edge Social Network Data Set used: soc-Epinions1

20. Active Sybil Attack (wiki-Vote) Social Network Data Set used: wiki-Vote

21. Hop Count: Advanced & Sybil Attack Social Network Data Set used: soc-Epinions1

22. Acknowledgements Dr. Matthew Wright Ph. D. Students: Mahdi Nasrullah Al-Ameen & Charles Gatz Dr. Yazdani University of Texas at Arlington National Science Foundation

23. Questions? Thank you for your time.