Network

The main objective of this research is to minimize delay in collaborative applications by setting tight bounds. Examples of collaborative applications include video-conferencing, distributed database replication, and online games. The efficiency of this project is analyzed and shown to be superior to its counterparts in the execution time. To provide an efficient heuristic to obtain a multicast sub network on an overlay network, given a source and a set of destinations that is within a specified maximum delay and a specified maximum variation in the delays from a source to the destinations.

In Wireless Sensor Networks, having two types of approaches non-clustering & clustering based. In both cases the prime role in network is energy consumption to transmit the data that will decide the life time of network. So this paper focused on the energy consumption. This research paper works for generation or formation of cluster & how to select the cluster head by which consideration of energy consumption should be less than non-clustering approach. In this research paper to create the cluster, implement the K-Mean algorithm to select the cluster head based on the nearest node to the location of center of cluster. This paper considers the sending energy consumption of each node in the whole network in both cases i.e. non-clustering & clustering.

Numerous schemes have been proposed for secure routing and Intrusion Detection for ad hoc net- works. Yet, little work exists in actually implementing such schemes on small handheld devices. In this paper, we present a proof-of-concept implementation of a secure rout- ing protocol based on AODV over IPv6, further reinforced by a routing protocol independent Intrusion Detection System (IDS) for ad hoc networks. Security features in the routing protocol include mechanisms for non-repudiation and authentication, without relying on the availability of a Certificate Authority (CA) or a Key Distribution Center (KDC). We present the design and implementation details of our system, the practical considerations involved, and how these mechanisms can be used to detect and thwart malicious attacks. We discuss several scenarios where the secure routing and intrusion detection mechanisms isolate and deny network resources to nodes deemed malicious.

In this paper, a distance based Cluster head selection algorithm is proposed for improving the sensor network life time. This protocol achieves a good performance in terms of lifetime by balancing the energy load among all the nodes. This clustering technique help to prolong the life of wireless sensor network, especially in hostile environment where battery replacement of individual sensor nodes is not possible after their deployment in the given target area. Therefore, the proposed technique to distribute the role of the cluster head (CH) among the wireless sensor nodes in the same cluster is vital to increase the lifetime of the network. This algorithm uses a distance based method for providing the cluster head selection. Clustering techniques also provide good load balancing. This paper based on the distance of nodes and elects the cluster head to be responsible collects the data from nodes, this implementation done in c- Language.

In today`s global scenario the demand of Wireless communication service is growing rapidly. In order to serve a high user population in a limited spectrum, using dense grids of microcells and picocells is one of possible schemes. While small cells relieve the capacity problem, frequent movements of mobile users across cell boundaries pose a big network control challenge: handover In personal communication networks (PCN) supporting network-wide handovers, new and handoff requests compete for connection resources in both mobile and backbone networks. Due to limited range of transceivers, mobile users can communicate only with base station that reside within the same microcell at any instant of time. The number of handovers during a call will increase, as the cell radii decreases, thus affecting Quality of Service (QoS). As the handoff rate increases, bandwidth management and traffic control strategy (call admission control, handover procedures etc) become more challenging problems in wireless ATM networks. Thus in a wireless environment, we need to consider two additional QoS parameters; dropping probability of handoff calls and blocking probability of new calls. Handoff calls require a higher congestion related performance i.e., blocking probability relative to new calls because forced call terminations due to handoff call blocking are generally more objectionable than new call blocking. In general, most of the previously proposed schemes for radio channel allocation in cellular networks reduce handoff call blocking probability substantially at the expense of increasing the new call blocking probability by giving higher priority to handoff calls over new calls in admission control. This reduces the total admitted traffic and results in inefficient utilization of wireless channels. The tradeoff between the new and handoff calls blocking probabilities should be defined. In this paper, a modified Hybrid scheme has been proposed for handover in ATM-based PCN, which combines reservation and queuing schemes for handoff calls. Also , the scheme assigns the handoff reserved channels to new calls depending on the locality principle in which the base station with the help of location estimation algorithm in the mobile location centre predicts the position of the mobile terminal. Here the FIFO and Measurement Based Priority Scheme (MBPS)queuing scheme are used. Thus the modified Hybrid Scheme is designed to have a remarkable reduction in forced termination Probability (FTP) along with to improve channel utilization while satisfying the QoS of the calls.

In Wireless Sensor Networks, cluster head is the key technology where nodes or motes the information transmit it to the base station. The energy consumption in a wireless sensor network can be reduced by allowing only some nodes to communicate with the base station. One way to support efficient communication between sensors is to organize the network into multiple groups, called clusters, with each cluster electing one node as the head of cluster. To support scalability, nodes are often grouped mostly non-overlapping clusters. This paper proposes a new design of an efficient clustering in wireless sensor head which is based on two level clustering. In two levels clustering approach instead of sensor nodes sends the data to cluster heads directly, each node sends data to their cluster head and then sends data to the base station.

A survey on mobile adhoc network networks have experienced strong growth due to their ability to provide an additional and complementary support for existing infrastructure communication systems. In such a network, routers are supposed to be fixed for short (e.g. public safety deployment) or long (e.g. network operator extension) period. This relative stability of infrastructure makes proactive routing protocols appropriate. One of the well known proactive routing protocols is OLSR (Optimized Link State Routing), which routing decisions are based on exchanges of topology information using all-to-all flooding of local information in order for each router to build a global knowledge of the topology. This study first goal is to improve the performance of topology information flooding in OLSR by introducing network coding techniques, which leads to a decrease of signaling overhead.

Turbo codes are one of the most powerful error correcting codes. In this paper focus is made on Bit Error Rate (BER) performance analysis of MAP, Log MAP and Max Log MAP turbo decoding algorithms in wireless AWGN channels. The research is investigated in several aspects to evaluate the performance of turbo codes in AWGN channel with different Signal to Noise Ratio (SNR), different generator polynomials and for different constraint lengths. The simulation results give some demonstrations that are valuable for the applications of turbo codes in AWGN channel with different SNRs.

The different layers of the network interface with each other for information transfer. In the cross-layer architecture the physical layer and medium access layer share information so that these information becomes available to the higher layers. The power control information of the physical layer and channel allocation information of the medium access layer are shared are shared with the upper network layers. Interference is a big challenge in wireless networks, so the communication links between two nodes use bit rate as the function parameter in the physical and access layer. The channel and network topologies vary from milliseconds to several seconds depending on the connection variation. The network control mechanism finds out the access control vector and the traffic forwarding decision to accomplish the quantitative performance objectives. The network performance objectives are overall throughput, power optimization and utility optimization of allocated resource rates. The cross-layer control algorithms with optimal performance are presented and analyzed. In this paper the detailed analysis and design techniques are presented.

Wireless sensor networks are generally deployed in inaccessible terrains for monitoring certain physical parameters like temperature, pressure etc. Sensor nodes sense the event and send the sensed data towards sink nodes using multi hop path. Since radio communication is expensive in terms of energy consumption, the sensor nodes typically spend most of their energy reserve on communication during data dissemination and retrieval. Storing data in-network at specific locations within WSNs that minimize packet transmissions reduces the energy consumption, and hence extends its lifetime. Considering limited storage space, limited energy and other constraints of sensors, a data caching mechanism for multi sink sensor networks is proposed. The proposed scheme Data Caching for query optimization in multi sink sensor networks (DCQOM) extracts the common sub tree of the networks first and then forms two caching zones: One from source node to common root and other from common root to sink nodes. The sensor nodes in the caching zones cooperate among themselves to form a larger cumulative cache. A token-based cache admission control scheme is devised, which ensures proximity of cached data closer to sink(s). Simulation results show that DCQOM provides substantial energy saving and data availability as compared to other caching schemes.