Abstract: With increasing number of wireless devices like
laptops, Wi-Fi Web Cams, network extenders, etc., a new kind of
problems appeared, mostly related to poor Wi-Fi throughput or
communication problems. In this paper an investigation on wireless
networks and it-s saturation in Vilnius City and its surrounding is
presented, covering the main problems of wireless saturation and
network load during day. Also an investigation on wireless channel
selection and noise levels were made, showing the impact of
neighbor AP to signal and noise levels and how it changes during the
day.
Abstract: Nowadays wireless technology plays an important
role in public and personal communication. However, the growth of
wireless networking has confused the traditional boundaries between
trusted and untrusted networks. Wireless networks are subject to a
variety of threats and attacks at present. An attacker has the ability to
listen to all network traffic which becoming a potential intrusion.
Intrusion of any kind may lead to a chaotic condition. In addition,
improperly configured access points also contribute the risk to
wireless network. To overcome this issue, a security solution that
includes an intrusion detection and prevention system need to be
implemented. In this paper, first the security drawbacks of wireless
network will be analyzed then investigate the characteristics and also
the limitations on current wireless intrusion detection and prevention
system. Finally, the requirement of next wireless intrusion prevention
system will be identified including some key issues which should be
focused on in the future to overcomes those limitations.
Abstract: In this paper, we first consider the quality of service
problems in heterogeneous wireless networks for sending the video
data, which their problem of being real-time is pronounced. At last,
we present a method for ensuring the end-to-end quality of service at
application layer level for adaptable sending of the video data at
heterogeneous wireless networks. To do this, mechanism in different
layers has been used. We have used the stop mechanism, the
adaptation mechanism and the graceful degrade at the application
layer, the multi-level congestion feedback mechanism in the network
layer and connection cutting off decision mechanism in the link
layer. At the end, the presented method and the achieved
improvement is simulated and presented in the NS-2 software.
Abstract: Wireless Sensor Networks (WSNs) are wireless
networks consisting of number of tiny, low cost and low power
sensor nodes to monitor various physical phenomena like
temperature, pressure, vibration, landslide detection, presence of any
object, etc. The major limitation in these networks is the use of nonrechargeable
battery having limited power supply. The main cause of
energy consumption WSN is communication subsystem. This paper
presents an efficient grid formation/clustering strategy known as Grid
based level Clustering and Aggregation of Data (GCAD). The
proposed clustering strategy is simple and scalable that uses low duty
cycle approach to keep non-CH nodes into sleep mode thus reducing
energy consumption. Simulation results demonstrate that our
proposed GCAD protocol performs better in various performance
metrics.