A Technique for Improving Security in Mobile Ad-hoc Networks

Transcription

1 A Technique for Improving Security in Mobile Ad-hoc Networks By Ahmed Mahmoud Abdel Mo men A Master Thesis Submitted to the Faculty of Computers and Information Cairo University Information Technology Under the Supervision of Prof. Imane Aly Saroit Ismail Dr. Haitham Safwat Kamal Hamza Cairo June 2011

2 Thesis Contributions 1. Present a comprehensive survey on secure and security enhanced multicast routing protocols in MANETs 2. Propose a novel atomic security approach for securing MAODV while reducing overhead and improving performance 3. Define three new multicast attacks on MAODV and demonstrate how the proposed framework can be extended to efficiently confront these new attacks.

3 Outline Secure Multicast Routing Protocols in MANETs The Concept of the Proposed Atomic Security Approach Proposed Atomic Security Framework for MAODV Protocol Identifying New Attacks on MAODV Protocol Performance Analysis Conclusion

4 Secure Multicast Routing Protocols in MANETs A mobile ad-hoc Network (MANET) is a self-organized network of mobile nodes that communicate through wireless links. Two nodes can communicate directly if they are within the communication range of each other; otherwise, multi-hop communication is used.

5 Secure Multicast Routing Protocols in MANETs (Cont.) Over the last decade, several security techniques have been designed for different environments and security objectives, to extend the capability of well-known ad hoc routing protocols. Depending on whether security is built-in or added, multicast routing protocols can be classified into two types: 1. Secure routing protocols: In which security techniques are embedded within the original design of the routing protocol. 2. Security-enhanced routing protocols: In which security techniques are added after the routing protocol is designed.

6 Secure Multicast Routing Protocols in MANETs (Cont.) Classification of Multicast Routing Protocols in MANETs: This figure shows five classification dimensions for multicast routing protocols in MANETs.

7 Secure Multicast Routing Protocols in MANETs (Cont.) Main Attacks on Multicast Routing protocols in MANETs: Compared to wired networks, MANETs are more susceptible to security attacks due to: 1. The lack of a trusted centralized authority. 2. The lack of trust relationships between mobile nodes. 3. Easy eavesdropping in the shared wireless medium of MANETs. 4. Dynamic network topology. 5. Energy and memory constraints of mobile devices.

8 Secure Multicast Routing Protocols in MANETs (Cont.) Main Attacks on Multicast Routing protocols in MANETs (Cont.): Attacks on multicast protocols can be divided into two broad categories: 1. Unicast attacks: In which the attacks aren't focused on the multicasting operations of the protocol, by another way, it attacks the unicast version of the protocol. 2. Multicast attacks: In which attacks are focused on the multicast operations of the protocol. These attacks are protocol dependent attacks in which are specially designed for specific protocol.

9 Secure Multicast Routing Protocols in MANETs (Cont.) Main Attacks on Multicast Routing protocols in MANETs (Cont.): This figure shows the different types of attacks that target the unicast as well as the multicast operations of multicast routing protocols in MANETs.

10 Secure Multicast Routing Protocols in MANETs (Cont.) Secure Multicast Routing Protocols in MANET: We summarize most common secure multicast routing protocols in MANETs, in which security techniques are embedded within the original design of the routing protocol, namely: SMGMP BSMR SEAMAN SORB ALMA For each protocol, we present a brief description, key limitation, and security challenges and evaluation.

11 Secure Multicast Routing Protocols in MANETs (Cont.) Security-Enhanced Multicast Routing Protocols in MANET: We summarize the most common security-enhanced multicast routing protocols in MANETs, which extend none-secured multicast routing protocols by adding security techniques after the design of the original protocols, namely: R-ODMRP SMRMN DIPLOMA CBMT SMMARP SE-MAODV EC-MAODV For each protocol, we present a brief description, key limitation, and security challenges and evaluation.

12 Secure Multicast Routing Protocols in MANETs (Cont.) Comparison of Secure Protocols Against Attacks: Attack Secure Multicast Routing Protocol SMGMP BSMR SEAMAN SORB ALMA Rushing x x Blackhole x x Neighbor x DoS x x x Wormhole x x MACT(J)-MTF MACT(P)-PART RREP(J)-PART GLS Not Applicable to These Multicast Protocols FLB GLP

13 Secure Multicast Routing Protocols in MANETs (Cont.) Comparison of Security-Enhanced Protocols Against Attacks: Attack Security-Enhanced Multicast Routing Protocol R-ODMRP SMRMN DIPLOMA CBMT SMMARP SE-MAODV EC-MAOV Rushing x x Blackhole x x x Neighbor x x DoS x x Wormhole MACT(J)- MTF MACT(P)- PART RREP(J)- PART GLS FLB GLP Not Applicable to These Multicast Protocols Not fully covered attack x x x x x x

14 Outline Secure Multicast Routing Protocols in MANETs The Concept of the Proposed Atomic Security Approach Proposed Atomic Security Framework for MAODV Protocol Identifying New Attacks on MAODV Protocol Performance Analysis Conclusion

15 The Concept of the Proposed Atomic Security Approach Traditional Functional Operation Security Approach: Conventional security techniques for multicast routing protocols focus on securing its functional operations. However, functional operations share several basic (atomic) operations. Thus, securing individual functional operations may increase overhead and reduce protocol performance. This leads to inefficient protocol security with low performance and high overheads due to security overhead redundancy.

16 The Concept of the Proposed Atomic Security Approach (Cont.) Traditional Functional Operation Security Approach (Cont.): Any multicast protocol operations can be stacked into three layers, namely functional operation, atomic operation categories, and atomic operation layer. In other words, the multicast functional operations are composed of several atomic operations that can be grouped into some logical categories called atomic operation categories.

17 The Concept of the Proposed Atomic Security Approach (Cont.) The Concept of the Proposed Atomic Security Approach: We address the drawbacks of the functional security approach by proposing an atomic operations security framework instead of functional operations security techniques. The proposed framework is modular and independent on functional operations and attacks. In which each module is dedicated with securing an atomic operation category in the multicast routing protocol.

18 The Concept of the Proposed Atomic Security Approach (Cont.) The Concept of the Proposed Atomic Security Approach (Cont.): This figure shows how atomic operations are arranged among functional operations that indicates the redundancy of atomic operations.

19 Outline Secure Multicast Routing Protocols in MANETs The Concept of the Proposed Atomic Security Approach Proposed Atomic Security Framework for MAODV Protocol Identifying New Attacks on MAODV Protocol Performance Analysis Conclusion

20 Proposed Atomic Security Framework for MAODV MAODV Case Study: Multicast Ad-hoc On-demand Distance Vector (MAODV) protocol is one of the well-known multicast routing protocol in MANET that dynamically constructs a shared multicast tree. RREQ, RREP, MACT, and GRPH message are the control message types utilized by MAODV. MAODV s multicast functional operations: Group Member Group Leader Tree Member

21 Proposed Atomic Security Framework for MAODV (Cont.) MAODV Case Study (Cont.): Typical security techniques for MAODV focus only on securing its functional operations (e.g., route discovery and link repair). Functional operations; however, do share several basic (atomic) operations. Thus, securing individual functional operations may increase overhead and reduce protocol performance. We propose the concept of securing atomic operations to exploit the redundancy among the functional operations of the MOADV protocol.

22 Proposed Atomic Security Framework for MAODV (Cont.) MAODV Case Study (Cont.): This figure shows how atomic operations in MAODV are arranged among functional operations that indicates the redundancy of atomic operations.

23 Proposed Atomic Security Framework for MAODV (Cont.) Known Attacks on MAODV Multicast Operations: Some attacks identied in literature targets to confront the multicast operations of MAODV. In which, effective and inefficient countermeasures are proposed to them that degrades the network performance such as: 1. Multicast Activation includes Join flag Multicast Tree Formation (MACT(J)- MTF) attack 2. Multicast Activation includes Prune flag Multicast Tree Partition (MACT(P)- PART) attack 3. Route Reply includes Join flag - Multicast Tree Partition (RREP(J)-PART) attack

24 Proposed Atomic Security Framework for MAODV (Cont.) MAODV Security Framework Based on Atomic Operations: We present three security modules which are the elements of our proposed atomic security framework, namely: 1. Control Messages Authentication Module 2. Group Certicate Module 3. Hop Count Authentication Module

25 Proposed Atomic Security Framework for MAODV (Cont.) MAODV Security Framework Based on Atomic Operations (Cont.): 1- Control Messages Authentication Module : Lightweight Hop-by-hop Authentication Protocol (LHAP) is used to authenticate the control packets (RREQ, RREP, GRPH and MACT). All control packets from unauthorized nodes are dropped, thus preventing them from propagating through the network. That will result that any unauthorized node can t launch attacks against the network.

26 Proposed Atomic Security Framework for MAODV (Cont.) MAODV Security Framework Based on Atomic Operations (Cont.): 2- Group Certificate Module : Timed Efficient Stream Loss-tolerant Authentication (TESLA) is an efficient end-to-end authentication scheme. TESLA is used in creating the group membership certificate. Every group member must be signed by the Certification Authority (CA) node. The group certificate is considered the key identity for the group member to join the multicast group. If an intermediate group member fails to verify the control message source node as a legitimate group membership certificate, it will drop it.

27 Proposed Atomic Security Framework for MAODV (Cont.) MAODV Security Framework Based on Atomic Operations (Cont.): 3- Hop Count Authentication Module: Hash chains is used to authenticate the hop count of tree nodes from the group leader. When a node sends a control message, it generates a random number called seed number. The hash field in the signature extension of the control packet is set to that seed number. The function used to compute the hash key is set in the hash function field. Since this field is signed, a forwarding node will only be able to use the same hash function which the sender has selected. If the receiver node cannot verify the control packet, then it will drop it.

28 Outline Secure Multicast Routing Protocols in MANETs The Concept of the Proposed Atomic Security Approach Proposed Atomic Security Framework for MAODV Protocol Identifying New Attacks on MAODV Protocol Performance Analysis Conclusion

29 Identifying New Attacks on MAODV This figure shows the different types of attacks that target the unicast as well as the multicast operations of the MAODV protocol. In this thesis, we identify and describe, three new attacks on multicast operations of MAODV namely: 1. Group Leader Selection (GLS) attack 2. False Link Breakage (FLB) attack 3. Group Leader Pruning (GLP) attack

30 Identifying New Attacks on MAODV (Cont.) 1- Group Leader Selection (GLS) attack: Malicious node deceives tree nodes to become a group leader. Group leader miss functionality tasks L A C M GRPH B D L A C M B V D Figure (a) shows that nodes (A, C and D) want to join the multicast tree. Malicious node (M) broadcast a GRPH message to them with hop count less than node (L). (a) (b) Tree Member Node Group Leader Mobile Node Malicious Node That will result constructing a new multicast tree leaded by node (M) in Figure (b).

31 Identifying New Attacks on MAODV (Cont.) 2- False link breakage (FLB) attack: B B Loop Malicious node initiates a link repair operation for unreal link breakage in the multicast tree. C RREQ (a) M RREQ A C M (b) A In Figure (a) : node M reports about virtual link breakage. Node (M) sends RREQ to nodes (A and C) with hop count greater than two (the real hop count from group leader). Tree Member Node Group Leader Mobile Node Malicious Node Nodes (A and C) believes that node (M) is a downstream node. New edges MC and MA are created causing loop in the multicast tree (Figure (b)).

32 Identifying New Attacks on MAODV (Cont.) 3- Group leader pruning (GLP) attack: Malicious node targets to prune the group leader from the tree. B L M MACT (P) (a) Tree partitioning A B L M (b) A In Figure (a): (M) listens to control packets outgoing from (L) to know its IP address and group ID. M uses this information to impersonate L. Tree Member Node Group Leader Mobile Node Malicious Node M sends MACT message to nodes (A and B) to indicate that node (L) wants to prune itself. Figure (b) shows that the multicast tree is now partitioned into two groups leaded by nodes (A and B).

33 Outline Secure Multicast Routing Protocols in MANETs The Concept of the Proposed Atomic Security Approach Proposed Atomic Security Framework for MAODV Protocol Identifying New Attacks on MAODV Protocol Performance Analysis Conclusion

34 Performance Analysis Packet Delivery Ratio (PDR) is used as a performance metric for both MACT(P)-PART and RREP(J)-PART attacks, whereas the total packets transmitted is used as a performance metric for MACT(J)- MTF attack. We make a comparison between secured MAODV using atomic approach and secured MAODV using functional approach. For each attack, we run four scenarios: 1. MAODV with no security and no attackers 2. MAODV with no security and two attackers 3. Secured MAODV using atomic approach and 2 attackers 4. Secured MAODV using functional approach and 2 attackers

35 Performance Analysis (Cont.) Atomic Framework Experimental Results on Known Attacks: 7 % No security, No attacker 3 % Atomic Security 24 % 6 % No security, No attacker 2.5 % Functional Security Atomic Security 22 % Functional Security No security, 2 attacker No security, 2 attacker MACT(P)-PART Attack degrades PDR by 22% compared to unsecured MAODV. Using functional approach, the PDR is degraded by 7%. Using atomic approach, the PDR is degraded by only 3%, that shows an improvement of 18%. RREP(J)-PART Attack degrades the PDR by 24% compared to unsecured MAODV. Using functional approach, the PDR is degraded by 6%. Using atomic approach, the PDR is degraded by only 2.5%, that shows an improvement of 14%.

36 Performance Analysis (Cont.) Atomic Framework Experimental Results on Known Attacks (Cont.): No security, 2 attacker Functional Security Functional Security 16 % 4 % Atomic Security No security, No attacker 60 % 300 % Atomic Security 66 % No security, No attacker MACT(J)-MTF Attack increases the number of bytes transmitted by 60% compared to unsecured MAODV. Using functional approach, this ratio is degraded to 16%. Using atomic approach, this ratio is degraded by only 4%, that shows an improvement of 20%. Compared to unsecured MAODV's byte overheads, the functional security approach increases the byte overheads by 300%. Whereas our atomic security framework increases the byte overheads by 66% only, that shows an improvement of 234%.

37 Performance Analysis (Cont.) Impact of The Atomic Security Framework on the New Attacks 4 % No security, No attacker 6 % No security, No attacker 34 % Secured, 2 attackers 35 % Secured, 2 attackers No security, 2 attacker No security, 2 attacker GLS attack degrades the PDR with 34% compared to unsecured MAODV. Using atomic framework, the PDR is degraded by only 4%, that shows an improvement of 88%. FLB attack degrades the PDR with 35% compared to unsecured MAODV. Using atomic framework, the PDR is degraded by only 6%, that shows an improvement of 83%.

38 Performance Analysis (Cont.) Impact of The Atomic Security Framework on the New Attacks (Cont.) 4 % No security, No attacker 28 % Secured, 2 attackers No security, 2 attacker GLP attack degrades the PDR with 28% compared to unsecured MAODV. Using atomic framework, the PDR is degraded by only 4%, that shows an improvement of 85%.

39 Conclusion Intensive simulation results show that the atomic approach can improve performance and decrease overheads under attack compared to functional security approach. It is shown that, compared to functional security approach, the proposed atomic approach improves the PDR under two known multicast attacks namely MACT(P)- PART and RREP(J)-PART attack by 18% and 14%, respectively, and decreases the number of bytes transmitted in MACT(J)-MTF attack by 20%. Moreover, the atomic security approach decreases the byte overheads by 234%. Simulation results shows that the proposed framework is a scalable framework to effectively and efficiently address future attacks on MAODV protocol.

40 Publications [1] A. M. Abdel Mo'men, H. Hamza, and I. Saroit, "New attacks and efficient countermeasures for multicast aodv", in HONET '07: Proceedings of the 7th annual international conference of High-Capacity Optical Networks and Enabling Technologies (HONET), Cairo, Egypt, December 2010, pp [2] A. M. Abdel Mo'men, H. Hamza, and I. Saroit, "A survey on security enhanced multicast routing protocols in Mobile Ad hoc Networks", in HONET '07: Proceedings of the 7th annual international conference of High-Capacity Optical Networks and Enabling Technologies (HONET), Cairo, Egypt, December 2010, pp [3] A. M. Abdel Mo'men, H. Hamza, and I. Saroit, "Secure Multicast Routing Protocols in MANETs, IEEE Communications Surveys & Tutorials (Under Review).

41 Thank You