Robust multiple frequency multiple power localization schemes in the presence of multiple jamming attacks

Localization of the wireless sensor network is a vital area acquiring an impressive research concern and called upon to expand more with the rising of its applications. As localization is gaining prominence in wireless sensor network, it is vulnerable to jamming attacks. Jamming attacks disrupt communication opportunity among the sender and receiver and deeply impact the localization process, leading to a huge error of the estimated sensor node position. Therefore, detection and elimination of jamming influence are absolutely indispensable. Range-based techniques especially Received Signal Strength (RSS) is facing severe impact of these attacks. This paper proposes algorithms based on Combination Multiple Frequency Multiple Power Localization (C-MFMPL) and Step Function Multiple Frequency Multiple Power Localization (SF-MFMPL). The algorithms have been tested in the presence of multiple types of jamming attacks including capture and replay, random and constant jammers over a log normal shadow fading propagation model. In order to overcome the impact of random and constant jammers, the proposed method uses two sets of frequencies shared by the implemented anchor nodes to obtain the averaged RSS readings all over the transmitted frequencies successfully. In addition, three stages of filters have been used to cope with the replayed beacons caused by the capture and replay jammers. In this paper the localization performance of the proposed algorithms for the ideal case which is defined by without the existence of the jamming attack are compared with the case of jamming attacks. The main contribution of this paper is to achieve robust localization performance in the presence of multiple jamming attacks under log normal shadow fading environment with a different simulation conditions and scenarios.

Performance Evaluation of Localization Accuracy for a Log-Normal Shadow Fading Wireless Sensor Network under Physical Barrier Attacks

Localization is an apparent aspect of a wireless sensor network, which is the focus of much interesting research. One of the severe conditions that needs to be taken into consideration is localizing a mobile target through a dispersed sensor network in the presence of physical barrier attacks. These attacks confuse the localization process and cause location estimation errors. Range-based methods, like the received signal strength indication (RSSI), face the major influence of this kind of attack. This paper proposes a solution based on a combination of multi-frequency multi-power localization (C-MFMPL) and step function multi-frequency multi-power localization (SF-MFMPL), including the fingerprint matching technique and lateration, to provide a robust and accurate localization technique. In addition, this paper proposes a grid coloring algorithm to detect the signal hole map in the network, which refers to the attack-prone regions, in order to carry out corrective actions. The simulation results show the enhancement and robustness of RSS localization performance in the face of log normal shadow fading effects, besides the presence of physical barrier attacks, through detecting, filtering and eliminating the effect of these attacks.

Studies of contents of norepinephrine and 5-hydroxytryptamine in brain--II. Effect of sodium barbitone and chlorpromazine

The effect of i.p. injection of sodium barbitone and chlorpromazine (25 mg/100 g body wt) on the levels of NE, 5-HT and body temperature was investigated in the brain regions of the field rat and the guinea-pig. Injection of the field rat with barbitone sodium or chlorpromazine provoked a general increase in the NE and 5-HT concentrations of the various brain parts. In guinea-pig variable changes were observed. Following injection with either of the two drugs, hypothermia was induced in the two animals at all of the time intervals examined.

Studies of contents of norepinephrine and 5-hydroxytryptamine in brain--I. Normal and cold exposure

The levels of NE and 5-HT were determined in different brain regions of the field rat and the guinea-pig under normal conditions and following cold exposure at 10 degrees C. Under normal conditions NE was found to be mainly accumulated in the midbrain while 5-HT exhibited its highest value in the pons plus medulla of both animals. Cold exposure of the field rat caused a general increase in NE concentrations while a general decrease occurred in the brain regions of the guinea-pig. 5-HT mostly decreased in the two animals. These changes in the amine levels could be related directly to the animal's response to cold.

Effect of cold exposure on brain 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in some vertebrate species

1. The changes in 5-HT and 5-HIAA levels were studied in the brain regions of Gerbillus pyramidum, Streptopelia senegalensis aegyptiaca and Agama stellio following exposure to cold. 2. In general, the 5-HT levels increased in the Gerbillus brain parts and decreased in those of Streptopelia. 3. Cold exposure in the Agama brain regions caused a transient decrease in the 5-HT levels of the cerebral hemispheres, midbrain and pons plus medulla after 6 hr and a general increase after 12, 24 and 48 hr. 4. It is concluded that cold exposure may be associated with increased activity of 5-HT ergic neurons and the rate of turnover of 5-HT to 5-HIAA.

Effect of heat stress on brain 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in some vertebrate species

1. The variations in 5-HT and 5-HIAA levels following heat exposure and split heat doses were determined in the different brain regions of Gerbillus pyramidum, Streptopelia senegalensis aegyptiaca and Agama stellio. 2. Heat exposure was found to be associated with an increase in the levels of the two indole compounds. 3. The 5-HT concentrations increased markedly in the three species following the first heat dose and decreased following the second dose in the various brain regions except in the cerebellum of Agama. 4. The increased 5-HT levels when animals are exposed to high temperature probably represent a response to activate heat-loss mechanisms and to depress heat production.