The paper analyses forwarding performance of IPsec gateway over the rage of offered loads. It focuses on the forwarding rate and packet loss particularly at the gateway's performance peak and at the state of gateway's overload. It explains possible performance degradation when the gateway is overloaded by excessive offered load. The paper further evaluates different approaches for obtaining forwarding performance parameters – a widely used throughput described in RFC 1242, maximum forwarding rate with zero packet loss and us proposed equilibrium throughput. According to our observations equilibrium throughput might be the most universal parameter for benchmarking security gateways as the others may be dependent on the duration of test trials. Employing equilibrium throughput would also greatly shorten the time required for benchmarking. Lastly, the paper presents methodology and a hybrid step/binary search algorithm for obtaining value of equilibrium throughput.

Visual cryptography is a method for protecting image-based secrets that has a computation-free decoding process. In this technique, numbers of shares have been generated from one image. The shares are sent through any channel to the receiver and the receiver can again produce original image by stacking all the shares in proper order. But, this method wastes a lot of bandwidth of the network. The techniques of generating shares have been used in several existing methods which are not unique. The different methods have been used in different types of images like binary, gray and color images. In this paper, a block based symmetry key visual cryptography algorithm has been proposed to convert image in encrypted form and decrypt the encrypted image into original form. The symmetric key has been generated from a real number. The encryption and decryption algorithm have been designed based on symmetry key. The algorithm with key has been used to encrypt image into single share and decrypt the single share into original image. The real number has been used to form the key may be predefined or may be sent by secure channel to the receiver. The proposed algorithm can be applied to any type images i.e. binary, gray scale and color images. A comparison has been made of the proposed algorithm with different existing algorithms like Ceaser cipher, transpose of matrix, bit comp, and transposition cipher based on the performance. The pixels distributed in original and share images have also been tested. Finally, it has shown that breaking of security level of proposed algorithm i.e. to guess the real number is huge time consuming.

Multipath routing mechanisms have been preferred over single path routing to provide parallel fail safe paths and to maximize throughput. Applying traditional shortest path metric for multipath route selection leads to traffic concentration at some nodes resulting in congestion, thereby causing performance degradation . Interference caused due to neighbouring node traffic is another factor that further limit its performance gains. Towards this, to ease out congestion and improve network resource utilization we devise a load balancing strategy that splits the load among multiple paths according to link quality. Link quality metric is formulated considering the current load condition , traffic interference and energy of the intermediate nodes. To study the effectiveness of the proposed load distribution method we compare it with another load balancing strategy that forwards traffic along one path ,found using our link quality metric and which switches over to alternate best path on route failure. Simulation results conducted show that proposed load splitting strategy is able to achieve improvement in performance in terms of reduced latency and improved throughput. Network Life time is also improved.

Network IDS perform a vital role in protecting network connection in the worldwide from malicious attack. Nowadays the recent experiment work related to inspecting the packet for network security that is a minimal amount of process overhead. In this work, analysis the network intrusion for packet inspection that is together the testing data which inspect only group of packet selected as sample predominantly from small flows and select first two packets and comparing with each other overall packets and create tabelazied for find out different malicious debuggers. This experiment results shows that overcome the existing work.

In this paper, we discuss the basic routing technique of ants and study the change in pheromone values at each node. Also the optimal paths can then be computed based on the shortest cumulative pheromone count between source and destination nodes. AntNet is a distributed multi-agent system inspired by the stigmergy model of communication observed in ant colonies. The ants or control packets collect information about the network conditions and are used to update and maintain the routing tables. Ants based routing is gaining more popularity because of its adaptive and dynamic nature. A number of Swarm Intelligence based, more specially Ant Colony Optimization (ACO) based routing algorithms are proposed by researchers. A version of ant routing protocol called AntNet has been implemented to work within the network simulator ns-2. Routing tables and Pheromone tables have been computed for each node in the network. On the basis of these tables we have tried to compute the shortest and most optimal path between source node and destination node.

Uncontrollable development of wireless and mobile communication technology aims to provide the seamless continuous connection to access various wireless technologies and to have connection with the best network which provides the best quality of service (QoS). Each application requires different QoS, so the network selection may vary accordingly. To achieve this goal and to select the best network for a mobile terminal when moving from one network to another, it is necessary to have a good decision making algorithm which decides the best network for a specific application that the user needs based on QoS parameter. This paper presents an overview of handoff types, handoff process, and classification of vertical handoff, parameters required, existing work and the comparison table.

An efficient threshold signature scheme solves the difficulties of the receiver to proof the approval of the document from the sender as well as detecting if the file has been altered by illegitimate parties. In these days there are plenty of signature schemes such as (t,n) threshold proxy signature scheme. The network is a shared medium so that the weakness security attacks such as eavesdropping, replay attack and modification attack. Thus, we have to establish a common key for encrypting/decrypting our communications over an insecure network. In this scheme, a (t,n) threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can't do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et al., Geng et al. and Fengying et al. with the performance of a scheme that has been proposed by the authors of this article earlier. In the proposed scheme, both the combiner and the secret share holder can verify the correctness of the information that they are receiving from each other. Therefore, the enhanced threshold proxy signature scheme is secure and efficient against notorious conspiracy attacks.