Comparison of Security Issues in Wireless Networks Meenakshi Gupta1 Manav Rachna College Of Engineering & Technology Faridabad, Haryana, India
[email protected]
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Abstract: Wireless networking is the preferred method for establishing new computer networks, more and more organizations and users are switching over to wireless communication because of its benefits such as flexibility and portability, increased productivity and low installation cost over wired networks. Therefore there are a growing number of regulatory requirements for the security of confidential data, specifically in government, financial and research and development environment. As the popularity of wireless network is increasing, the need to make them secure also increases. In this paper we’ll do the comparison of security issues in routing protocols and performance evaluation of various routing protocols. Keywords: Ad hoc routing protocols, secure routing, DSDV, AODV, DSR and attacks.
I INTRODUCTION These days’ wireless technologies have gained lots of attention, due to their advances and benefits. Ad hoc networks are one such technology, which provides a paradigm for self organized networks. There are two approaches for wireless communication between two or more hosts. The first is centralized cellular network in which each mobile is connected to one or more fixed base stations. A second decentralized approach consists based of an ad hoc network between users that wish to communicate between each other, due to the more limited range of the mobile terminal, this approach requires mobile nodes not only source and destination but also forward packets between other mobiles. In preceding sections we’ll explain the ad hoc networks, comparison ad hoc routing protocols and comparison of security issues in secure routing protocols using commonly identified attack patterns.
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Sanjana Malhotra2 Manav Rachna College Of Engineering & Technology Faridabad, Haryana, India
[email protected] II IDEAS AND METHODS
Ad hoc Networks: Ad hoc network is a collection of wireless mobile nodes dynamically forming a temporary network without the use of any existing infrastructure or centralized administrator. Ad hoc networks have the advantage of being quickly deployable as they do not require any existing infrastructure. In ad hoc networks routing protocols are central. Routing Algorithms: There are four routing algorithms. The idea of these protocols is used in ad hoc networks to implement routing protocols. 1. Link state routing: here each node maintains a complete view of topology with a cost per each link. Each node periodically broadcasts its link costs of out going links to other nodes by using flooding. Each node updates its view and apply shortest path algorithm for choosing next hop for each destination. 2. Distance vector routing: Each node only monitors the cost of its out going links. Instead of broadcasting the information to all nodes, it periodically broadcasts to each of its neighbors an estimate of the shortest distance to every other node in the network. The receiving nodes use this information and update their routing tables by applying shortest path algorithm. 3. Source routing: Routing decisions are taken at the source and the packets carry along the complete they should take. 4. Flooding: The source sends the Information to all neighbors who continue to sending it to their neighbors etc. By using sequence numbers for the packets , a node is able to relay a packet only once.
Routing Protocols: Routing protocols are classified into two categories: Proactive: Destination sequence Distance Vector Routing(DSDV) Wireless Routing Protocol (WRP) Source Tree Adaptive Routing(STAR) Reactive: Dynamic Source Routing(DSR) Temporally ordered Routing Algorithm(TORA) Ad hoc On Demand Distance Vector Routing(AODV) Comparison of Routing Protocols: In this section we are defining three routing protocols i.e. DSDV, AODV and DSR. And compare their performance by calculating their throughput and packet delivery ratio. DSDV: Destination Sequenced Distance Vector routing protocol is one of the first protocol proposed for ad hoc wireless networks. It was developed based on the distributed Bellman-Ford algorithm where each node maintains a table that contains the shortest distance and the first node on the shortest path to every other node in the Network. Each node contains its own routing table that indicates the destination. Each node periodically broadcasts its routing updates. A sequence number is used to tag each route. It shows the freshness of a route i.e. the node with higher sequence number is more preferable. If a node detects a broken destination link, it sets it hop number to infinity and its sequence number updated to odd number, even numbers correspond to sequence numbers of connected path. AODV: It does not require nodes to maintain routes to destination that are not actively used.It uses the concept of sequence numbers in DSDV to avoid routing loops. The protocol uses different messages to discover and maintain links: Route Request RREQs), Route Reply RREPs) and Route errors(RERRs). These message types are received via UDP and normal IP header processing applies. When an intermediate node receives a RREQ, it sends a route reply (RREP) if it is either the destination or if it has a route to the destination with
corresponding sequence number greater than or equal to that contained in the RREQ. The intermediate node also stores the previous node information in order to forward the data packet to this next node towards the destination. DSR: Designed for mobile ad hoc networks with up to two hundred nodes with possibly high mobility rate. The protocol works “on demand” basis i.e. without periodic updates. The protocol is composed of route discovery and route maintenance. • Route discovery: In the route discovery phase the source node establishes a route by flooding route request packets (RREQ). The RREQ contains the source IP address and destination IP address. The neighbor nodes accumulate the traversed path into the RREQ and broadcast to its next neighbor if the current node is not the destination node. Once the destination node receives the RREQ it concatenates the source route in a Route Reply packet (RREP) and replies on the same path as in RREQ. • Route Maintenance: Route maintenance is carried whenever there is a broken link observed in the specific route to the destination. When the packets are forwarded through a specific route, each node sends the packet to the next node in the route and the next node acknowledges the packet received. When a broken link is observed in the destination path the broken link will not acknowledge to the packet transmitted by the neighbor node, and the node send a route error message (RERR) to the source node. The source then responds to this RERR and stops sending the next packets and will look in its route cache for alternative routes and follow the next available path. III EXPERIMENTAL RESULTS AND ANALYSES Performance Evaluation: Simulation environment and parameters: • Number of nodes used for the simulation: 50 • Maximum Number of connection: 10 • Network Density dimensions: 500 x 500 meters • Application data payload size: 512/kb • Mobility pattern: Uniform • Link bandwidth: 2 mbps • Traffic pattern: CBR
• Simulation time: 100 seconds • Maximum node Speed: 20meters/sec Throughput: Security Issues in Routing protocols: Ad hoc networks are extremely vulnerable to attacks due to their dynamically changing behavior, no fixed security infrastructure and open communication medium. To address these vulnerabilities secure routing protocols have been proposed. But secure routing in ad hoc networks is a challenging task. Currently many researchers are working on them and every time proposing a variety of secure routing protocols. Each protocol fulfills different security requirements and counter measures against attack patterns. In next sections we are going to define some secure routing protocols and also give a comparison of them on the basis of already identified attack patterns on routing protocols. Secure Routing Protocols: There are several secure routing protocols proposed basing on the working principles of the earlier ad hoc protocols. SEAD: Secure Efficient Distance vector Routing. Ariadne SRP: Secure Routing Protocol ARAN: Authenticated routing for Ad hoc Network SAODV: Secure Ad hoc On-Demand Distance Vector Routing SAR: Security- Aware Routing Protocol
Packet Delivery Ratio: Routing Protocol
Packet Sent
Packets Received
Delivery Ratio
DSDV
1114
814
0.7307
AODV
1127
1110
0.9849
DSR
1113
1091
0.9802
SEAD: SEAD was developed based on DSDV and incorporates One-Way Hash function to authenticate in the routing update mechanism in order to enhance the routing security. Securing a proactive protocol is harder than securing a reactive protocol due to the existence of predefined routes. Distance vector protocols encapsulate the route information into a hop count value and a next hop. An attacker cannot create a valid route with a larger sequence number that it received due to the properties of hash function. Routing table overflow attacks are possible in SEAD. Spoofing black hole, tunneling and DoS attacks are possible in SAED. Ariadne: Ariadne was developed based on the Destination Source Routing (DSR). Ariadne uses MAC s and shared keys between nodes to
authenticate between nodes and use time stamps for packet lifetime. Ariadne prevents spoofing attacks with time stamps. The use of source routes prevents loops, since a packet passing through only legitimate nodes will not be forwarded into a loop due to time stamps.
IV Conclusion: From above simulation results, we can say that the throughput of DSDV is greater than that of DSR and AODV, but the packet delivery ratio of AODV is best as compared to DSDV and DSR. From above simulation, DSR is proved best because it has both good throughput and packet delivery ratio. And after comparing the secure routing protocols on the basis of already identified attack patterns, we can say that SAR, SAODV and ARAN are better than other secure routing protocols.
SRP: SRP was developed based on Destination Source Routing (DSR). The intermediate nodes participating in the route discovery measure the frequency of queries received from their neighbours and maintains a priority ranking inversely proportional to the query rate. So the malicious compromised nodes participating in the network are given least priority to deal with. The security analysis is similar to Ariadne as it is based on DSR protocol.
REFERENCES
ARAN: It uses public key cryptography and a central certification authority server for node authentication and neighbor node authentication in route discovery. DoS attacks are possible with compromised nodes. Tunneling attacks are also possible. Spoofing attacks are prevented by ARAN through node level signatures. SAODV: SADOV uses a central key management in its routing topology. Digital signatures are used to authenticate at node level and hash chain is used to prevent the altering of node counts. Tunneling and warm hole attacks are possible. Replay attacks are prevented here due to the use of sequence numbers.
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SAR: SAR was developed using a trust-based framework. Each node in the network is assigned with a trust level. So the attacks on this framework can be analyzed based on trust level and message integrity. Here security is evaluated as trust level and message integrity.
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Comparison of secure routing protocols:
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Attack pattern Ad hoc security protocol
DOS (Denial of service)
Tunn eling
Spoofin g
Warm hole
Black hole
Routing tables overflow attack
SEAD
Yes
Yes
Yes
Yes
Yes
Yes
Ariadne
Yes
Yes
No
Yes
No
SRP
Yes
Yes
No
Yes
No
ARAN
Yes
Yes
No
Yes
No
SAODV
Yes
Yes
No
Yes
No
SAR
Yes
Yes
No
Yes
No
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