this paper proposes a new smart antenna beamforming scheme based on electronically steerable parasitic array radiator (espar). the proposed method is capable of providing better capacity compared to the conventional espar. the termination of each antenna element in this structure comprises a pin diode in addition to a varactor. using pin diode besides the varactor provides more degrees of freed...

in this paper, an anomaly detection method in cluster-based mobile ad hoc networks with ad hoc on demand distance vector (aodv) routing protocol is proposed. in the method, the required features for describing the normal behavior of aodv are defined via step by step analysis of aodv and independent of any attack. in order to learn the normal behavior of aodv, a fuzzy averaging method is used fo...

content discovery is one of the fundamental issues that determines the architecture and performance of content distribution networks based on peer-to-peer (p2p) networks. to administrate the costs and discoveries, peers of a p2p network communicate with each other by one or more overlay layers. the condition of node’s relations in overlay networks, have a great impact in efficiency of networks....

many performance evaluations for ieee 802.11distributed coordination function (dcf) have been previouslyreported in the literature. some of them have clearly indicatedthat 802.11 mac protocol has poor performance in multi-hopwireless ad hoc networks due to exposed and hidden nodeproblems. although rts/cts transmission scheme mitigatesthese phenomena, it has not been successful in thoroughlyomit...

in recent years, routing has been the most focused area in ad hoc networks research. on-demand routing in particular, is widely developed in bandwidth constrained mobile wireless ad hoc networks because of its effectiveness and efficiency. most proposed on-demand routing protocols are built and relied on single route for each data session. whenever there is a link disconnection on the active ro...

ad hoc networks are multi-hop wireless networks without a pre-installed infrastructure. such networks are widely used in military applications and in emergency situations as they permit the establishment of a communication network at very short notice with a very low cost. video is very sensitive for packet loss and wireless ad-hoc networks are error prone due to node mobility and weak links. h...

The ad hoc grid is a spontaneous organization of cooperating heterogeneous nodes into a logical community without a fixed infrastructure and with only minimal administrative requirements. Resource management for ad hoc grids is challenging due to the participation of heterogeneous, dynamic, autonomous and ephemeral grid nodes. The paper proposes an ad hoc grid resource management system, the pr...

Mobile ad hoc networks will often be deployed in environments where the nodes of the networks are unattended and have little or no physical protection against tampering. The nodes of mobile ad hoc networks are thus susceptible to compromise. The networks are particularly vulnerable to denial of service (DOS) attacks launched through compromised nodes or intruders. In this paper, we present a ne...

In this paper, we discuss security issues and their current solutions in the mobile ad hoc network. Ad hoc networks are a new wireless network for mobile hosts. Owe to the vulnerable nature of the mobile ad hoc network, there are many security threats that effected the development of wireless network. We evaluate the accessible in the mobile ad hoc networks and find out attacks than the convent...