Sohini Roy et al. / Journal of Computing Technologies Vol 2, Issue 4 ISSN 2278 – 3814 © 2013 JCT JOURNALS. ALL RIGHTS RESERVED 5 CRBSR: A CRT-RSA-BELLMENFORD BASED SECURE ROUTING Sohini Roy #1 , Ditipriya Sinha #2 # Department of Information Technology,Calcutta Institute of Engineering and Management India 1 roysohini266@gmail.com 2 ditipriyasinha87@gmail.com Abstract— Mobile Ad-hoc networks are a collection of autonomous nodes with dynamic network structure without any centralized control. Security in such a network is one of the main challenges to the researchers. To address security in MANET we have adopted a method based on RSA, CRT and BELLMEN- FORD ALGORITHM. Together with encryption and decryption method we have focused on finding of secure routes from a set of available routes and selection of the most stable and energy efficient route from a source to a destination. From the performance analysis of our protocol it is proved that it gives better performance than many of the existing protocols. Combination of RSA, CRT and BELLMANFORD makes our proposed routing protocol secured and robust. Keywords— CRT, LATCH, MONITOR, WEIGHT_REQ, Trust value I. INTRODUCTION The networks that offer unrestricted mobility of the nodes without any underlying infrastructure are known as Mobile Ad hoc Networks. The mobile nodes are interconnected by multi- hop communication paths or radio links and all the nodes themselves act as routers, servers, clients etc. The main features of MANETs include dynamic network topology, bandwidth constrained variable capacity links and energy constrained operations. The radio links as well as the mobile nodes are vulnerable to different attacks. Confidentiality is also an important aspect of the security goal of MANETs which ensures that certain information is never disclosed to unauthorized entities. Integration of information which guarantees that the transferred information is unaltered and authentication that enables two communicators to identify each other should be also taken under consideration. Thus, providing security to such a network is one of the main challenges. The traditional authentication, key distribution and intrusion detection methods are too inefficient to be used in energy constrained devices in MANETs. In our protocol we propose a security mechanism that avoids the network communication. We have adopted an RSA based encryption and CRT based decryption technique for secure communication through the network. To distribute the keys in the network or broadcasting RREQ messages we have taken the help of BELLMEN- FORD algorithm. As a new node enters the existing network, it is not considered as a trusted node and thus it is monitored by a trusted node of the network to guarantee its permission of entering the network. To avoid the intrusion of malicious nodes, we have provided a secure route selection method from a set of all probable routes between a source and a destination by means of a key known as LATCH which is generated with the help of CRT. Our algorithm thus uses a combined concept of CRT, RSA and BELLMEN-FORD algorithm to offer a secure communication scheme in MANETs. II. RELATED WORK This section reviews several security solutions in mobile ad- hoc network. Specially this section investigates different key generation model, trust based model and secure routing model, since these models demonstrate the gradual progress in the literature. A. MANET Security Breaches: Threat to a Secure Communication Platform [1] provides a view of overall security breaches present in the Ad-hoc Networks together with several proposed routing protocols. The paper mentions that communication between two nodes in a network is completely based on mutual trust and thus to provide security to a network there should be a routing protocol which encapsulates all the necessary security mechanisms. The paper categorizes two kinds of attacks in MANETs. One of them is Active attack and the other kind of attack is the Passive attack, which do not interfere with the running operations in the network rather it performs eavesdropping of data exchanged via the concerned nodes.. The designing issues for secure routing in MANETs are also mentioned by the paper. B. A Highly Secured Approach against Attacks in MANETS [2] identifies the major reason to address security in MANETs as the use of wireless links that are prone to attacks. The paper proposes a highly secure approach to identify different types of attacks in MANETs using a semantic security mechanism which is highly impossible to break. The approach of this paper deals mainly with the attacks in the network layer by considering the misbehaviour of nodes which drop and delay packets despite agreeing to forward them during route discovery.