Trust-Based Security Technique to Curb Cooperative Black Hole Attacks in Mobile Ad Hoc Networks using OTB-DSR Protocol in NS-3

The advent of mobile technology led to the emergence of Mobile Ad-hoc networks (MANETs). These networks have no infrastructure and central authority. Nodes in MANETs act as both routers and hosts. MANET nodes join and leave the network at will making the network topology dynamic. MANETs are prone to both passive and active security attacks. Blackhole is a denial of service attack under active attacks. Blackhole nodes work in collaboration forming cooperative black hole attacks. The attacks drop or redirecting data packets on transit. Cooperative blackhole attacks are dangerous in operations where communication is critica

Host choice and multiple blood feeding behaviour of malaria vectors and other anophelines in Mwea rice scheme, Kenya

<p>Abstract</p> <p>Background</p> <p>Studies were conducted between April 2004 and February 2006 to determine the blood-feeding pattern of <it>Anopheles </it>mosquitoes in Mwea Kenya.</p> <p>Methods</p> <p>Samples were collected indoors by pyrethrum spay catch and outdoors by Centers for Disease Control light traps and processed for blood meal analysis by an Enzyme-linked Immunosorbent Assay.</p> <p>Results</p> <p>A total of 3,333 blood-fed <it>Anopheles </it>mosquitoes representing four <it>Anopheles </it>species were collected and 2,796 of the samples were assayed, with <it>Anopheles arabiensis </it>comprising 76.2% (n = 2,542) followed in decreasing order by <it>Anopheles coustani </it>8.9% (n = 297), <it>Anopheles pharoensis </it>8.2% (n = 272) and <it>Anopheles funestus </it>6.7% (n = 222). All mosquito species had a high preference for bovine (range 56.3–71.4%) over human (range 1.1–23.9%) or goat (0.1–2.2%) blood meals. Some individuals from all the four species were found to contain mixed blood meals. The bovine blood index (BBI) for <it>An. arabiensis </it>was significantly higher for populations collected indoors (71.8%), than populations collected outdoors (41.3%), but the human blood index (HBI) did not differ significantly between the two populations. In contrast, BBI for indoor collected <it>An. funestus </it>(51.4%) was significantly lower than for outdoor collected populations (78.0%) and the HBI was significantly higher indoors (28.7%) than outdoors (2.4%). Anthropophily of <it>An. funestus </it>was lowest within the rice scheme, moderate in unplanned rice agro-ecosystem, and highest within the non-irrigated agro-ecosystem. Anthropophily of <it>An. arabiensis </it>was significantly higher in the non-irrigated agro-ecosystem than in the other agro-ecosystems.</p> <p>Conclusion</p> <p>These findings suggest that rice cultivation has an effect on host choice by <it>Anopheles </it>mosquitoes. The study further indicate that zooprophylaxis may be a potential strategy for malaria control, but there is need to assess how domestic animals may influence arboviruses epidemiology before adapting the strategy.</p

Design and Implementation of Resilient Cooperative Bait Detection Technique to Curb Cooperative Black Hole Attacks in MANETs Using DSR Protocol

Mobile Ad-hoc networks (MANETs) are unique type of wireless networks that are infrastructureless and with no centralised management. Nodes in MANETs act as both routers and hosts. The nodes are free to join and leave the network. Routes are established by use of special routing protocols. Mobility of nodes makes the network topology constantly dynamic. The unique characteristics of MANETs make their security a challenging endeavor. MANETs are prone to a range of security attacks such worm hole, Sybil, black hole, among others. Blackhole is a form of denial of service (DoS) attack. The black hole nodes work in association forming cooperative black hole attacks that drop or redirecting data packets. This compromises the communication process in mission critical areas. The paper proposes a Resilient Cooperative Bait Detection Technique (RCBDT) using DSR protocol to curb collaborative black hole attacks in MANETs. The proposed technique uses source node address as the bait address. Further, RCBDT uses an algorithm that checks nodes energy levels before engaging them in packet transmission. The technique was designed, implemented and simulated in Network Simulator Version 3(NS-3). The proposed technique was compared with Cooperative Bait Detection Scheme (CBDS) and Extended Cooperative Bait Detection Scheme (ECBDS). Simulation results indicate that the proposed technique is superior to benchmark techniques in terms of Packet Delivery Ratio (PDR), End-to-End Delay and Routing Overheads

Optimized Trust-Based DSR Protocol to Curb Cooperative Blackhole Attacks in MANETs Using NS-3

MANETs Communication relies on special routing protocols that make security a challenging endeavor. MANETs are open to a range of active and passive attacks; black hole attack is an active attack affects the network layer. Cooperative black hole attack is a form of denial of service attack comprised of more than one black hole nodes that collaborate in order to drop data packets during communication process. In our study, we used the concept of trust to extend the DSR protocol in order to mitigate cooperative black hole attacks that leads to loss of data packets. The paper proposes an Optimized Trust-Based Dynamic Source Routing protocol. The proposed protocol integrates dynamic trust and friendship functions in the standard DSR protocol. The proposed protocol was designed, implemented and simulated in Network Simulator version 3 (NS-3). Simulation results indicate that the proposed protocol is superior to standard Dynamic Source Routing (DSR) protocol and Ad hoc On Demand Vector (AODV) protocols used as the benchmark protocols; in terms of packet delivery ratio, routing overhead and end-to-end delays and throughput used as performance metrics. The Optimized Trust-Based DSR protocol had a packet delivery ratio of above 95%, routing overhead of about 4.75% and an end-to-end delay of between 0.9 seconds and 1.65 seconds and a throughput of 95.6 Kbps

Trust-Based Security Technique to Curb Cooperative Blackhole Attacks in Mobile Ad Hoc Networks using OTB-DSR Protocol in NS-3

The advent of mobile technology led to the emergence of Mobile Ad-hoc networks (MANETs). These networks have no infrastructure and central authority. Nodes in MANETs act as both routers and hosts. MANET nodes join and leave the network at will making the network topology dynamic. MANETs are prone to both passive and active security attacks. Blackhole is a denial of service attack under active attacks. Blackhole nodes work in collaboration forming cooperative black hole attacks. The attacks drop or redirecting data packets on transit. Cooperative blackhole attacks are dangerous in operations where communication is critical. This paper proposes a Trust-Based Resilient Cooperative Bait Detection Technique (TB-RCBDT), an integration of the Resilient Cooperative Bait Detection Technique (RCBDT) and Optimized Trust-Based Dynamic Source Routing (OTB-DSR)

Antimycobacterial Activity, Cytotoxicity and Phytochemical Screening of Organic Extracts of Commiphora Africana Stem Bark from Kenya

Tuberculosis (TB) is a communicable disease that kills approximately three million people annually. Efforts to treat the disease have been made difficult due to the development of drug-resistant strains and co-infection with HIV/AIDS. There is a need to develop new, inexpensive, safe, and effective anti-TB drugs. Commiphora africana (C. africana, Burseraceae) is a very useful plant and has been known to treat several ailments. The plant contains various secondary metabolites and has been found to possess many pharmacological activities such as antifungal, antimicrobial, antioxidant, hepatoprotective, anti-inflammatory and anti-ulcer effects. The study aimed at screening the extracts for their antimycobacterial activity against Mycobacteria smegmatis; cytotoxicity in Vero cells; qualitative phytochemical analysis and Thin Layer Chromatography (TLC) profiling. Phytochemical screening revealed the presence of alkaloids, flavonoids, terpenoids, coumarins, phenols, saponins, sapogenins, and tannins. The dichloromethane and ethyl acetate extracts of C. africana stem bark were the most active extracts against the M. smegmatis strain used with a minimum inhibitory concentration (MIC99) of 1.30 and 2.60 mg/mL, respectively. Cytotoxicity studies revealed that most of the extracts had CC50>20 µg/mL thus considered safe. However, hexane extract of C. africana stem bark showed CC5