PROJECT DOMAIN : NETWORK SECURITY Project Members : M.Ananda Vadivelan & E.Kalaivanan Department of Computer Science

SECURE DATA TRANSMISSION IN NETWORK COMMUNICATION AGAINST ACTIVE ATTACKERS USING RC4 ALGORITHM

ABSTRACT Most of the existing work on key generation from wireless fading channels requires a direct wireless link between legitimate users so that they can obtain correlated observations from the common wireless link. This paper studies the key generation problem in the two-way relay channel, in which there is no direct channel between the key generating terminals. We propose an effective key generation scheme that achieves a substantially larger key rate than that of a direct channel mimic approach. Unlike existing schemes, there is no need for the key generating terminals to obtain correlated observations in our scheme. We also investigate the effects of an active attacker on the proposed key generation protocol. We characterize the optimal attacker’s strategy that minimizes the key rate of the proposed scheme. Furthermore, we establish the maximal attacker’s power under which our scheme can still achieve a nonzero key rate.

EXISTING SYSTEM In certain applications, however, two terminals might be far away from each other, and hence there is no direct channel between them. The two-way relay channel, in which two terminals are connected through a relay, is a basic setup that models this scenario. The key generation from the two ways relay channel problem was considered, which proposed several interesting schemes to circumvent the issue that there is no direct channel to provide the necessary common randomness. The basic idea of these schemes is to create a virtual direct link from which these two terminals can obtain channel estimates and then apply the approach. For example, in the amplify forward (AF) scheme discussed, Alice transmits a training sequence to the relay, which then sends a scaled version of the received noisy signal to Bob. From the received signal, Bob can obtain an estimate of the product of two channel gains: the one from Alice to the relay, and the one from the relay to Bob.

DISADVANTAGE Active node tries to send attack signals to interrupt the key generation process. It is very difficult to evaluate the key rate. No randomizes key generation. The key generation from the two ways relay channel problem was not considered

PROPOSED SYSTEM We propose a new scheme for the key generation in the two-way relay channel by adopting a scheme proposed in our recent work. Instead of trying to mimic a direct channel as done, in the proposed scheme, the two terminals involved do not need to obtain correlated estimates. Similarly, the relay and Bob can establish a pair-wise key using the channel linking them. The advantages of this approach are: 1) Eve does not obtain any information about the channel gains used for the key generation, hence our scheme obtains a much higher key rate; 2) It is very easy to evaluate the key rate of the proposed scheme; and 3) Our scheme can be easily extended to multiple antenna case, and the key rate scales linearly with the number of antennas. The second main contribution of the paper is to consider the active attacker scenario. In this paper, we assume that Eve’s goal is to send attack signals to minimize the key rate of the proposed scheme. The effects of an active attacker are twofold: 1) Eve can corrupt signals received by legitimate nodes, and hence reduce the correlations between the signals observed by legitimate users; and 2) By controlling the signals observed by the legitimate users, Eve has partial information about the observations used for the key generation. Both of these two effects will decrease the key rate.

ADVANTAGE It is very easy to evaluate the key rate. Characterizes the maximum attacker’s power. Reduce the correlations between the signals observed by legitimate users. Reduce the attack file rate.

SYSTEM SPECIFICATION HARDWARE SPECIFICATION: PROCESSOR: Intel(R) Pentium(R) Dual-Core Processing RAM:1GB RAM HARD DISK:20 GB SOFTWARE SPECIFICATION OPERATING SYSTEM:Windows XP,Windows2007 (32Bit Original) ENVIRONMENT: Visual Studio.NET 2005 or 2008 or 2010.NET FRAMEWORK :Version 2.0 or Version 3.0 or Version 4.0 LANGUAGE:C#.NET BACK END:MS-SQL-Server 2000

MODULE DESCRIPTION: This project contains four major module.those modules are follow 1.Energy based keying module. 2.Crypto module. 3.Packet transmission and reception module. 4.Performance analysis module.

ENERGY BASED KEYING MODULE The energy-based keying process involves the creation of dynamic keys. Contrary to other dynamic keying schemes, it does not exchange extra messages to establish keys. A sensor node computes keys based on its residual energy of the sensor. The key is then fed into the crypto module. CRYPTO MODULE The crypto module in EBEK employs a simple encoding process, which is essentially the process of permutation of the bits in the packet according to the dynamically created permutation code generated via RC4. The encoding is a simple encryption mechanism adopted for EBEK. However, EBEK ’ s flexible architecture allows for adoption of stronger encryption mechanisms.

PACKET TRANSMISSION AND RECEPTION MODULE The Packet transmission and reception module handles the process of sending or receiving of encoded packets along the path to the sink. And also get the acknowledgement from the receiver side to conform the delivery status of the node. PERFORMANCE ANALYSIS MODULE In this module we are going to consider the false injection and eavesdropping of messages from an outside malicious node. And also check a routing path is established from the sources in the event region to the sink. We assume that the path is fixed during the delivery of the data and the route setup is secure. So the sensor network is densely populated generate reports for the same event. This module will help to analyze the performance of the nodes.

DATA FLOW DIAGRAM: ENERGY-BASED ENCRYPTION AND KEYING USER SENDER RELAY RECEIVER AUTHETICATION UNMAE, PWD EBEK LEVEL: 0

SENDER Dynamic Key Generation Packet Encryption Performanc e Analysis Packet Send User File Size, Random Key Random Key, RC4 Encryption Key, Encrypted packet Key, File Size Uname, Pwd EBEK LEVEL: 1

RELAY Checking Key Packet Decryption Packet Send User Key Random Key, RC4 Decryption Message Uname, Pwd LEVEL: 2

LEVEL: 3 RECEIVE R User Message Uname, Pwd Receive Message

Authentication SECRET KEY GENERATION IN THE TWO-WAY RELAY CHANNEL WITH ACTIVE ATTACKERS Energy Based Keying Relay Receiver Packet Size Calculation Key Gen based on packet size Packet Send to relay Key Verify Decrypt the packet Send to Receiver Send Ack ARCHITECTURE DESIGN: