Qos-Aware Handover Scheme for Hierarchical Mobile Ipv6 Using Context Transfer with Link Layer Trigger

The incredible rate that the Internet is growing has made recently for the convergence of the various networks into an unified IP based architecture. The challenge in such a complex network is to provide a seamless support. Seamless handover is a combination of fast and smooth handover. Thus seamless handover will basically offer lower latency and packet drops. In this study, we examine a QoS-aware handover scheme based on Hierarchical Mobile IPv6 architecture. Enhancements to the scheme to improve seamless support are investigated. The two main elements added to this system are the use of link layer trigger and context transfer. The detection and triggering of handover is an important functionality of handover, which has a strong impact on its performance in terms of handover latency and packet loss. Link layer trigger shortens the time for handover detection and therefore decrease the overall service interruption caused by handover. The main purpose of context transfer is to reduce the time when a particular flow does not receive the contracted QoS due to a handover situation. This is achieved by transferring in advance the information to the access router where the mobile node is expected to be attaching next in order to maintain the QoS for that flow. Without context transfer, the access router takes some time to recover this information due to the exchange of signaling information. The time wasted here can be harmful for real-time applications that require timely delivery and a constant service level. Apart from this, context transfer is also a way to preserve scarce wireless bandwidth between mobile node and the access router, as it does not use this wireless link to reinitiate QoS information as done previously in the QoS-aware handover scheme. The proposed scheme performance is proven by means of simulation and an analytical study, whereby handover delay and packet loss are the main performance parameters. Simulation results have proved that the proposed scheme performs better by decreasing the handover delay by 75 % and packet loss rate by 16.3 %. Further the analytical study done validates the results obtain from simulation by proving analytically the decrease in handover delay, packet loss and utilization of bandwidt

Qos-Aware Handover Scheme Using Context Transfer With Link Layer Trigger For Hierarchical Mobile IP

New applications such as VoIP, video on demand and video conferencing, are gaining popularity in the Internet. Although the Internet is based on a best effort delivery mechanism, the introduction of these applications has placed a new demand on the Internet to provide guaranteed Quality of Service (QoS)

Mathieu functions and its useful approximation for elliptical waveguides

The standard form of the Mathieu differential equation is d2ydη2+(a−2qcos2η)y=0 where a and q are real parameters and q > 0. In this paper we obtain closed formula for the generic term of expansions of modified Mathieu functions in terms of Bessel and modified Bessel functions in the following cases: (i)Ce1'(ξi,γ12)Ce1(ξi,γ12)(ii)Fey1'(ξi,γ12)Fey1(ξi,γ12)(iii)Gey1'(ξi,γ12)Gey1(ξi,γ12)(iv)Ce1'(ξi,γ22)Ce1(ξi,γ22)(iv)Se1'(ξi,γ22)Se1(ξi,γ22). Let ξ0 = ξ0, where i can take the values 1 and 2 corresponding to the first and the second boundary. These approximations also provide alternative methods for numerical evaluation of Mathieu functions

An investigation on the use of ITU-R P.1411-7 in IEEE 802.11N path loss modelling

Free space path loss modelling is a model used to model path loss propagation for Wireless Local Area Networks. In some cases, the estimation of path loss by the FSL model can be inaccurate as FSL modelling does not take into account the effect of multipath propagation. The International Telecommunication Union Recommendation, ITU-R P.1411-7 provides prediction methods for the planning of short-range outdoor radio communication systems and radio local area networks in the frequency range 300 MHz to 100 GHz. This recommendation further proposes a location variability correction, ρ, which models the standard deviation of field strength due to small scale fading. This paper investigates the feasibility of using the ITU-R P.1141-7 Recommendation to estimate the path loss for 802.11n signals experienced by pedestrians in a suburban environment. Received signal strengths were collected from field experiments, and the measured path loss was compared with estimated path loss values. The results show that for areas with high levels of small scale fading, the ITU-R P.1141-7 was able to estimate the path loss for IEEE 802.11n signals with a higher accuracy of 5-7 dB than the FSL model

Model Dispersion Analysis of Circular Waveguide in Normal and Reverse Boundary Condition

The dispersion characteristics of the circular step index fiber with helical windings between the core-cladding region is investigated. Sheath helix is wounded between the core and cladding using two directions, namely in the clock wise and anticlockwise direction. Substituting the field components into the modified boundary conditions due to the addition of the helical windings the modal characteristics are derived for both fibers. Representations of the helical windings are done by using normal boundary conditions and reverse boundary conditions. The Eigen equation is obtained in the form of Bessel functions and modified Bessel functions for both the waveguides. The dispersion curves are plotted for two specific pitch angles ψ=0° and ψ=90 for each fiber and the results are compared. The direction of wrapping the helical material results in a change in the dispersion properties with regards to the way the modes propagate in both fibers. These changes are seen by the presents and absence of (1) band gap,(2) splitting of modes and (3) adjacent modes depending on the direction and pitch angle of the helical windings. Results obtained in this work suggest that direction and pitch angle of the helical winding are parameters that are able to control the behavior of the modes

I-Bin: Weight Based IoT Smart Recycling Scheduler for Guarded Neighbourhood

Overpopulation and lack of awareness are the main causes of poor waste management. While existing research in waste management employs current technology such as the Internet of Things, it lacks emphasis on residential centric type of waste management system. This project designs a weight based scheduling system for a guarded neighbourhood using Arduino Uno, load cells and plastic bins which are then incorporated with WiFi to send waste weight information in real time to cloud for monitoring. Design verification tests such as the linearity test and non- repeatability test showed less than 1 percent standard deviation error. A Proof of Concept test was conducted to test the system's performance at a guarded residential area. Analysis of test showed that an average of 0.0966 kg of recyclable waste was collected per house. Based on the results also, it is predicted that approximately 483 kg of waste can be effectively collected from 10 residential areas using the I-Bin system. Residents tend to dispose waste after office hours and scheduling more waste collection frequency after office hours will lead to increased revenue for the recycling company

Analysis of the propagation characteristics of circular step-index fibre with new sheath helix boundary condition

A circular step-index fibre with a helical winding on the core-cladding boundary is proposed and investigated analytically with a new type of boundary condition. Using cylindrical coordinate system (r, , z), new boundary conditions are imposed and longitudinal field components are obtained. The equation involves Bessel and modified Bessel functions. Numerical computations are made. Dispersion curves are obtained for different pitch angles. The main effect of the helical winding on the characteristics is to introduce band gaps

Comparative study of boundary conditions with helix

This paper presents a comparative study of dispersion characteristics of the circular waveguide with helical windings. Our waveguide is doubly unconventional in the choice of reverse boundary condition, in the choice of normal boundary condition and further with the presence of sheath helix between the core and cladding parameters. Two methods of winding the helix between the core and cladding are considered namely from right to left and left to right. Through mathematical analysis using field components and boundary conditions the modal characteristics are derived for both conditions. Normal boundary condition and reverse boundary conditions are used respectively to represent the helical windings. Here the characteristic equation is obtained in the form of Bessel and modified Bessel for both waveguides. Using the modal characteristic equation the dispersion curves are plotted for numerous angles and wavelengths. We find that the method of wrapping the helical material has significant effect on the dispersion properties with regards to the way the modes propagate