134,192 research outputs found
Geometric and Signal Strength Dilution of Precision (DoP)Wi-Fi
The democratization of wireless networks combined to the emergence of mobile
devices increasingly autonomous and efficient lead to new services. Positioning
services become overcrowded. Accuracy is the main quality criteria in
positioning. But to better appreciate this one a coefficient is needed. In this
paper we present Geometric and Signal Strength Dilution of Precision (DOP) for
positioning systems based on Wi-Fi and Signal Strength measurements.Comment: International Journal of Computer Science Issues (IJCSI), Volume 3,
pp35-44, August 200
Security in Wireless Sensor Networks: Issues and Challenges
Wireless Sensor Network (WSN) is an emerging technology that shows great
promise for various futuristic applications both for mass public and military.
The sensing technology combined with processing power and wireless
communication makes it lucrative for being exploited in abundance in future.
The inclusion of wireless communication technology also incurs various types of
security threats. The intent of this paper is to investigate the security
related issues and challenges in wireless sensor networks. We identify the
security threats, review proposed security mechanisms for wireless sensor
networks. We also discuss the holistic view of security for ensuring layered
and robust security in wireless sensor networks.Comment: 6 page
Atomic-SDN: Is Synchronous Flooding the Solution to Software-Defined Networking in IoT?
The adoption of Software Defined Networking (SDN) within traditional networks
has provided operators the ability to manage diverse resources and easily
reconfigure networks as requirements change. Recent research has extended this
concept to IEEE 802.15.4 low-power wireless networks, which form a key
component of the Internet of Things (IoT). However, the multiple traffic
patterns necessary for SDN control makes it difficult to apply this approach to
these highly challenging environments. This paper presents Atomic-SDN, a highly
reliable and low-latency solution for SDN in low-power wireless. Atomic-SDN
introduces a novel Synchronous Flooding (SF) architecture capable of
dynamically configuring SF protocols to satisfy complex SDN control
requirements, and draws from the authors' previous experiences in the IEEE EWSN
Dependability Competition: where SF solutions have consistently outperformed
other entries. Using this approach, Atomic-SDN presents considerable
performance gains over other SDN implementations for low-power IoT networks. We
evaluate Atomic-SDN through simulation and experimentation, and show how
utilizing SF techniques provides latency and reliability guarantees to SDN
control operations as the local mesh scales. We compare Atomic-SDN against
other SDN implementations based on the IEEE 802.15.4 network stack, and
establish that Atomic-SDN improves SDN control by orders-of-magnitude across
latency, reliability, and energy-efficiency metrics
Improving energy efficiency and quality of service in an integrated wireless-optical broadband access network
Exponential growth in the volume of wireless data, boosted by the growing popularity of mobile devices such as smart phones and tablets, is forcing telecommunication industries to rethink network design, and focus on developing high capacity mobile broadband networks. Accordingly, researchers have undertaken developmental work for an integrated wireless-optical broadband access network (WOBAN). Passive optical networks (PONs) and fourth generation (4G) wireless networks are two major candidate technologies for the WOBAN. PON is a wired access technology, well-known for its high capacity, whereas 4G is a wireless broadband access technology, popular for its ease of deployment and ability to offer mobility. Integration of PON and 4G technologies, as a wireless-optical broadband access network, offers advantages such as extension of networks in rural areas, support for mobile broadband services, and rapid deployment of broadband networks. However, these two technologies have different design architectures for handling broadband services which require Quality of Service (QoS), for example, 4G networks use traffic classification for supporting different QoS demands whereas PON does not differentiate between traffic types. This integrated network must also be energy efficient, as a green broadband access network, without hindering QoS. While these technologies both use sleep mode, they differ in their power saving mechanisms.
This thesis first addresses a QoS solution for the incompatibility between these technologies. Service class mapping is proposed in Chapter 3 for the integrated WOBAN, based on the M/G/1 queuing model supported by an innovative priority scheduler. Once class mapping is deployed, a power saving mechanism can be devised by exploiting traffic differentiation. Specifically, a class-based strategy is proposed which helps optimise the sleep period for the terminal units of the optical network, without compromising QoS.
Since the optical network involves control and terminal nodes, both of which consume power, this thesis proposes an energy efficient mechanism that involves both components. In contrast, other published strategies (Chapter 2) have only considered the terminal units. Chapter 4 presents the mechanism for enabling global sleep (control and terminal nodes) and local sleep (terminal nodes), based on the available traffic\u27s class structure. This mechanism enables sleep for different components within the bandwidth allocation by adapting the switching between predefined polling cycle lengths.
As the WOBAN is comprised of both wireless and optical parts, a dynamic resource management mechanism is needed which responds to changing daily traffic patterns across a green integrated network. Consequently, Chapter 5 proposes a mechanism which dynamically adapts the polling cycles, of the optical and wireless parts of the network, to the changing traffic volume and class composition. Tailored sleep durations for the components of the WOBAN are facilitated within the resource management regime, as these components differ in their ability to function efficiently if management of the sleep periods is not responsive to the changing traffic volumes and class composition.
This dissertation creates new knowledge by seamlessly integrating the two parts of WOBAN and introducing differentiated, class-based sleep for the components of the hybrid network to help realise a green WOBAN
Developing an Efficient DMCIS with Next-Generation Wireless Networks
The impact of extreme events across the globe is extraordinary which
continues to handicap the advancement of the struggling developing societies
and threatens most of the industrialized countries in the globe. Various fields
of Information and Communication Technology have widely been used for efficient
disaster management; but only to a limited extent though, there is a tremendous
potential for increasing efficiency and effectiveness in coping with disasters
with the utilization of emerging wireless network technologies. Early warning,
response to the particular situation and proper recovery are among the main
focuses of an efficient disaster management system today. Considering these
aspects, in this paper we propose a framework for developing an efficient
Disaster Management Communications and Information System (DMCIS) which is
basically benefited by the exploitation of the emerging wireless network
technologies combined with other networking and data processing technologies.Comment: 6 page
A Secure Lightweight Approach of Node Membership Verification in Dense HDSN
In this paper, we consider a particular type of deployment scenario of a
distributed sensor network (DSN), where sensors of different types and
categories are densely deployed in the same target area. In this network, the
sensors are associated with different groups, based on their functional types
and after deployment they collaborate with one another in the same group for
doing any assigned task for that particular group. We term this sort of DSN as
a heterogeneous distributed sensor network (HDSN). Considering this scenario,
we propose a secure membership verification mechanism using one-way accumulator
(OWA) which ensures that, before collaborating for a particular task, any pair
of nodes in the same deployment group can verify each other-s legitimacy of
membership. Our scheme also supports addition and deletion of members (nodes)
in a particular group in the HDSN. Our analysis shows that, the proposed scheme
could work well in conjunction with other security mechanisms for sensor
networks and is very effective to resist any adversary-s attempt to be included
in a legitimate group in the network.Comment: 6 page
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