1. Security Issues in Ant Routing Weilin Zhong

2. Outline Swarm Intelligence AntNet Routing Algorithm Security Issues in AntNet Possible Solutions

3. Swarm Intelligence Biology Swarms Social Insect Characteristics Complex Group Behaviors Simple Individual Behaviors Local Communication and Interaction No Leader or Coordinator

4. Swarm Intelligence Complex Group Behaviors Nest Building Wasp Nets

5. Swarm Intelligence Complex Group Behavior - Ant Forage Model

6. Swarm Intelligence How can simple individuals achieve complex group behaviors? --The Intelligence of biological swarm lies on its interaction network

7. Swarm Intelligence Two Kinds of Interactions Locally Direct Interaction A member interacts with its neighbors Indirection Interaction -- Stigmergy Interaction intermediate by the common environment

8. Swarm Computing Model Computing Swarm Computing Swarm is a collection of large number of small computational members Examples: Sensor Networks, Multi-agent System, Amorphous Computer System Characteristics Myriad numbers of elements. Decentralized control Autonomous members Sophisticated global behaviors Adaptive and self-organized

9. AntNet Routing Algorithm Swarm Intelligence In General Network Routing Problems Learn from the Ant Forage Model AntNet Routing Algorithm A Distributed Adaptive Routing Algorithm Mobile Multi-agent Systems Inspired by the stigmergy model in ant colonies

10. AntNet Routing - Agents Two kinds of Agents(Ant Packets) Forward Ant explores the network and collects information when reaches the destination, changes into backward ant Backward Ant goes back in the same path as forward ant update routing tables for all the nodes in the path

11. AntNet Routing --- Agents Agents behaviors Backward Ant 1 2 3 4 Forward Ant (N1,T1) (N2,T2) (N1, T1) Forward Ant (N1,T1) (N2,T2) (N3,T3) Forward Ant (N1,T1) (N2,T2) (N3,T3) (N4, T4) Forward Ant Backward Ant

12. Probabilistic Routing Table Local Statistics Model AntNet Routing- Router 1 1 2 3

13. Buffer Lookup and forwarding Forward_ANT FIFO1 FIFO2 Out[ ] Port1 Port2 FIFO1 FIFO2 FIFO1 FIFO2 Port N Schedule r Backward_ANT AntNet Router Structure Data Packet Updating

14. Measure Trip Time AntNet Routing 1 2 3 4 Forward Ant (N1,T1) (N2,T2) (N1, T1) Forward Ant (N1,T1) (N2,T2) (N3,T3) Forward Ant (N1,T1) (N2,T2) (N3,T3) (N4, T4) Forward Ant Backward Ant VT4 = 0 Backward Ant VT3 = VT4 + Local_VT Backward Ant VT2 = VT3 + Local_VT Backward Ant VT1 = VT2 + Local_VT Local_VT = Channel_Tran_Prop_delay + Load_Dependent_Processing_Delay

15. AntNet Routing Algorithms Updating Routing Table Reinforcement Factor r = C1 * ( W best /T) + C2 * Var Increase the probability of the channel that backward ant comes from P’ = P + r * (1 - P) Decrease the probability of the other channels P’ = P * ( 1 - r)

16. AntNet Routing Algorithm A Simple Network Example 10423 0 0 0 0 0 1 1 1 1 12 2 2 3

17. Security Issues in AntNet Threats untrustworthy hosts Malicious Agents Attack Goals increase the packet latency --- mislead packets to a longer path Break down a critical node --- mislead packets to a certain node to overload it Drop Data Packets --- mislead packets to a malicious node

18. Security Issues Untrustworthy Hosts forward data packet to a wrong direction delay data packet generate a bursts of ant packets to reinforce bad path generate false ant packets to make good path bad Malicious Agents carried false trip time information

19. Possible Solutions Authentication Mechanism problem: expensive Time Stamp or Sequence Number on Agent Better Adaptive Model for quick recovery form the impact of malicious agent Other solutions?...