Trust based Multicast routing in Mobile Ad hoc Network

1. November 11, 2011 Trust based Multicast routing in Mobile Ad hoc Network Vadakkumuri V Aboobacker [Aboo] Student Id: 41418220 Supervisor: Dr. Rajan Shankaran Macquarie University ITEC810 Project - Semester 2, 2011 Trust based Multicast in Mobile Ad hoc Networks

2. Summary • Introduction • Multicast in MANET • Trust in MANET • Trust management frameworks in MANET • Trust based multicast frameworks • A new trust based extension for MAODV multicast protocol • Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

3. Introduction • Introduction Multicast in MANET Trust in MANET Trust management frameworks in MANET Trust based multicast A new trust based extension for MAODV multicast protocol Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

4. Background • Characteristics • Self organising • Self configuring • Distributed and cooperative network operations • No fixed infrastructure • Highly dynamic multi-hop topology • Applications • Battlefields • Emergency rescue services • Business conferences or school class rooms Trust based Multicast in Mobile Ad hoc Networks

5. Project aim • Identify the routing related challenges in MANETs, especially with multicast routing • Security and efficiency • Identify the solutions available to address these challenges • Trust management frameworks • Trust based multicast routing • Design a trust based extension to MAODV multicast routing protocol Trust based Multicast in Mobile Ad hoc Networks

6. Significance • Increasing popularity of MANETs • Evolution from a military based networks in to commercial space • A lot of research issues have surfaced due to peculiar characterises of MANETs, especially in the area of routing • Multicast is a very important feature required in MANETs • Optimize node and network utilization • Various researches are focused around unicast routing • Only little attention has been given to trust based multicast Trust based Multicast in Mobile Ad hoc Networks

7. Analysis methodology • Study the security challenges in unicast and multicast routing in MANET • Multicast techniques • Analyse MAODV multicast protocol in depth • Study the trust management frameworks in MANETs • General trust • Importance of trust in MANETs • Various trust management frameworks • Apply trust based schemes to multicast routing • Study existing security based and trust based solutions • Used AODV and MAODV as candidates for analysis • Propose a new scheme for trust based multicast Trust based Multicast in Mobile Ad hoc Networks

8. Multicast in MANET Introduction • Multicast in MANET Trust in MANET Trust management frameworks in MANET Trust based multicast A new trust based extension for MAODV multicast protocol Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

9. Multicast in MANET • Traditional Link State and Distance Vector protocols are not directly applicable • Dynamic topology changes • Varying link and node conditions • Nodes moving, joining and leaving • Co-operative routing • Every node is a potential router! • Multicast techniques • Reactive and proactive protocols • Mesh based and tree based • Focus on a tree based protocol – Multicast Adaptive On demand Distance Vector Protocols (MAODV) Trust based Multicast in Mobile Ad hoc Networks

10. Multicast Adaptive On demand Distance Vector protocol (MAODV) • A tree based approach • All the nodes in the multicast groups are in a multicast tree • Only one path exists between two nodes of the tree • The goal is to graft a branch to the nearest (least hop count) leaf node of the tree • Tree management is a distributed approach Trust based Multicast in Mobile Ad hoc Networks

11. Multicast Adaptive On demand Distance Vector protocol (MAODV) • Group leader • First node in the multicast group • A node may assume the leadership if no route reply (RREP) received for a multicast group • Timeout and retries • Maintains the route sequence number for the multicast group • Periodic Group Hello messages • Repairing portioned groups and broken links • Features: • Reactive protocol • Hop count for route selection process (Distance Vector) • Broadcast id to avoid duplicate protocol messages • Route sequence number to indicate freshness of a route Trust based Multicast in Mobile Ad hoc Networks

12. Multicast Adaptive On demand Distance Vector protocol (MAODV) • Route discovery: • Broadcasts RREQ protocol message to every neighbours • Neighbours check their routing table • Replies (RREP) if a route exists • Otherwise re-floods the request to its neighbours • Nodes record the route back to the source node to relay RREP message back to source • The requested node receives many routes from different neighbouring nodes • Chooses the best route using hop count and uses MACT to establish only one branch to the nearest leaf node Trust based Multicast in Mobile Ad hoc Networks

13. Multicast Adaptive On demand Distance Vector protocol (MAODV) RREP RREQ MCAST MCAST RREP RREQ RREQ RREP RREP RREQ RREP RREQ RREQ RREQ RREQ RREQ RREP RREP New network node initiating route discovery A regular network node Existing group member + router Link Group leader Branch of the multicast tree Node acting as route alone

14. Security related Challenges in Multicast • Similar security threats as in fixed networks • DoS, unauthorized disclosure, unauthorized modification, non-repudiation, unauthorized access, etc • Certain attacks are more aggravated, especially DoS attacks due to: • Co-operative routing (every node is a router) • Highly dynamic network topology • Resource limited nodes • Unreliable communication media • Counter measures are difficult: • Protection should be implemented in every node • Limitation on node resources • No trusted third party • Basis of key management • Difficult to do authentication and authorization Trust based Multicast in Mobile Ad hoc Networks

15. Trust in MANET Introduction Multicast in MANET • Trust in MANET Trust management frameworks in MANET Trust based multicast A new trust based extension for MAODV multicast protocol Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

16. Trust in MANET • The network nodes are generally unpredictable • Due to varying node and link conditions • Malicious intentions including selfish nodes • No central administration • Trust can be viewed as an expectation on how the node going to behave in future • Networking functions such as routing are simplified if the nodes are predictable (good or bad) • Trust is can be considered as an ingredient to solve security related challenges in MANETs • Achieve co-operation • The more trustworthy a node is, the more reliable it is Trust based Multicast in Mobile Ad hoc Networks

17. Trust in MANET – Problems with Security services in MANET • Traditional means of protection using security services: • Authentication, authorization, non-repudiation, integrity, confidentiality • Can not reliability detect node’s conditions • Node movements, battery levels, noise levels, etc • Relies on a central trusted third party (certifiers and KMC) • Implementation is difficult in resource limited nodes • Security services put additional burden on network nodes • Relies on the trustworthiness of network infrastructure • Physical security of routers • Administration by a competent and central autonomous body

18. Trust in MANET – Why? • Identifies malicious or selfish activities of nodes • Using trust management framework • More trustworthy a node, the more reliable it is • Considers varying network and node conditions into account • Node movements, conditions of nodes and communication media • Better for dynamic environments such as MANET • Reduces cryptographic computational requirements • Better solution for resource limited nodes • Compliments security services and vice versa • Many distributed key management schemes are based on trust • Robust systems can be built by combining trust and security services. Trust based Multicast in Mobile Ad hoc Networks

19. Trust management frameworks in MANET Introduction Multicast in MANET Trust in MANET • Trust management frameworks in MANET Trust based multicast A new trust based extension for MAODV multicast protocol Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

20. Trust management frameworks in MANET • Requirements: • Highly dynamic • Selfish and malicious nodes do exist • No unreasonable computational requirements • Continuous, short lived and calculated online • No central trusted third party • Must be a distributed approach • Predicts the nodes behaviour in future – trustworthiness • Based on certain evidences such as certificates or keys (evidence based) • Based on past experiences (reputation based) Trust based Multicast in Mobile Ad hoc Networks

21. Trust management frameworks in MANET – Reputation based • Most prevalent technique in MANET • All nodes collect and keep historical interactions • Good and bad behaviours • Also collect opinions from other nodes • Quantify the collected evidences into trust metrics • Used in decision making process such as selection of routes • Various techniques used for calculation • Simple approach: The ratio of good interactions and total interactions in a window period • Complicated approaches using statistical and probability techniques Trust based Multicast in Mobile Ad hoc Networks

22. Trust based multicast Introduction Multicast in MANET Trust in MANET Trust management frameworks in MANET • Trust based multicast A new trust based extension for MAODV multicast protocol Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

23. Problems with routing protocols in MANETs • Designed mainly to take care of: • Dynamic nature of the network • Scalability • to be implemented in resource limited nodes • Security is an after thought! • Assumes all the nodes are: • Trustworthy, properly administered and have the capacity to perform networking functions • This assumption could be safe in traditional fixed and wireless networks (dedicated routers) • Every node is a router in MANET! Trust based Multicast in Mobile Ad hoc Networks

24. Techniques to secure routing infrastructure - Security based AODV • Uses signatures to protect protocol messages • Uses certificates • Provides authentication and integrity • Problems: • Requires cryptographic computations • Uses certificates but PKI is not defined • Do not consider ambient route conditions • A secure node does not mean that it is reliable! • Varying conditions of link and nodes along the path to the destination Trust based Multicast in Mobile Ad hoc Networks

25. Trust based multicast • Uses a trust management framework • Uses trust values while admitting node to multicast group • Uses the trust value during route selection process • Shortest path is not sufficient due to highly dynamic nature of networks • Trust can include ambient route conditions • Trust can also include security related attributes of the nodes along the path • Trust also can be used as a decision point to re-evaluate an existing route Trust based Multicast in Mobile Ad hoc Networks

26. Techniques to secure routing infrastructure – Trust based AODV • No cryptography involved • Distributed trust management approach • There are various schemes available • Some assumes most network nodes are reliable • Some uses only self derived node trust while others also use recommendations from other nodes • Whilst some schemes considers node trust, others use route trust to consider the reliability of all the nodes in the path • Based on the analysis, there is room for improvement! Trust based Multicast in Mobile Ad hoc Networks

27. A new trust based extension for MAODV multicast protocol Introduction Multicast in MANET Trust in MANET Trust management frameworks in MANET Trust based multicast • A new trust based extension for MAODV multicast protocol Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

28. A new approach for trust based MAODV multicast routing protocol • Trust management framework • Reputation based trust management • Uses Node trust and route trust • Self derived and recommendations • Uses confidence value • Only reliable trusts are advertised • Rely on recommendations based trust if confidence value is low • Relies more on self derived trust as the confidence value increases Trust based Multicast in Mobile Ad hoc Networks

29. Node trust • Calculates based on recent interactions (good and bad) • Used for route selection process • Used for admission in to multicast tree • Node trust is the combination of self derived trust and recommendations. • Rely on recommendation based trust if confidence value is low • Relies more on self derived trust as the confidence value increases Trust based Multicast in Mobile Ad hoc Networks

30. Node trust Trust based Multicast in Mobile Ad hoc Networks

31. Node trust Trust based Multicast in Mobile Ad hoc Networks

32. Route trust • Route trust • Calculates based on the send vs. received packet counts along the route • Also uses the trust value of individual nodes along the routes to derive the route trust • Re-evaluates the selected routes periodically (9) Is used initially during the initial route discover process Trust based Multicast in Mobile Ad hoc Networks

33. Route selection process • Protocol messages RREQ, RREP are modified to include trust values • The route with highest trustworthy nodes as wells as the least hop count is selected. • Configurable weights for considering hop count and trust Trust based Multicast in Mobile Ad hoc Networks

34. Conclusion and future directions Introduction Multicast in MANET Trust in MANET Trust management frameworks in MANET Trust based multicast A new trust based extension for MAODV multicast protocol • Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks

35. Conclusion • Trust is an important concept in MANETs due to the co-operative nature of the network (Infrastructure less and self organising nature) • Security based solutions are difficult in resource limited devices and are more prone to DoS attacks • Security based approaches cannot take care of the dynamic nature of the network and varying route conditions • Trust based solutions could detect malicious nodes, selfish nodes and also to improve cooperation in the network • Increases network throughput and utilization • Trust could also complement security based solutions and vice versa. • Trust based routing (unicast and multicast) is considered very ideal in MANETs to secure the routing infrastructure Trust based Multicast in Mobile Ad hoc Networks

36. Future directions • Security should not be an after thought in designing network protocols • More significance to trust based schemes • Key management is crucial for security services • Centralized key management not applicable • More attention to distributed key management is required • Compared to fixed networks, MANET is very far from being popular • Challenges associated with MANETs will continue to be hot research topic for years to come • Fine tuning of proposed trust management framework and trust based multicast • Simulations and experiments Trust based Multicast in Mobile Ad hoc Networks

37. Questions and discussions Introduction Multicast in MANET Trust in MANET Trust management frameworks in MANET Trust based multicast A new trust based extension for MAODV multicast protocol Conclusion and future directions Trust based Multicast in Mobile Ad hoc Networks