An investigation of cryptographically generated address (CGA)-based authentication for mobile IPv6

It is well known that the most promising approach to solving the problem of authentication in a mobile IPv6 network is to use CGA-based authentication. The only drawback is that CGA algorithms can be computationally expensive. This study analyses the performance of the CGA generation algorithm and proposes changes to impose a minimal computational security while maintaining reasonable performance. This study also compares the use of Rivest Shamir Adleman (RSA) signatures with the Merkle Signature Scheme (MSS) for generating CGA Signatures. It finds that using MSS significantly improves the key generation time. However, more work needs to be done to improve both the CGA generation algorithm and MSS in order to make CGA-based authentication an attractive option in MIPv6 setups

Video coding : MPEG standards

Moving Picture Coding Exports Group (MPEG) refers to a whole family of international standards for compression of audio-visual digital data. The most well known are MPEG series which are also formally known as ISO/IEC-13818 and ISO/IEC-14496 [ISO/IEC,2007]. The most important aspects are summarized as follows: The MPEG- I standard was published 1992 with aim of providing VHS quality trough a bandwidth of 1.5 Mb/s, which allowed to playa video in real time from a CD-ROM. The frame rate in MPEG - I is locked at 25(PAL) fps and 30(NTSC) fps respectively. Furthermore, MPEG- I was designed to allow a fast forward and backward search and synchronization of audio and video. A stable behavior, in cases of data loss, as well as allow computation times for encoding and decoding was reached, which is important for symmetric applications, like video telephon

Generalized discrete fourier transform based minimization of PAPR in OFDM systems

Orthogonal frequency division multiplexing OFDM is a preferred technique in digital communication systems due to its benefits of achieving high bit rates and its ability to resist multipath effect over fading channels. However, high peak to average power PAPR ratio of the OFDM transmitted signal is a main drawback in OFDM systems. In this paper, the nonlinear phase from the theory of generalized discrete Fourier transform (GDFT) is used to improve the performance of the partial transmit sequence (PTS) scheme which is one of the techniques used to reduce PAPR. This technique divides the input OFDM block into a number of sub-blocks. IFFT is taken for each sub-block, then the output phase is rotated by coefficients to produces minimum PAPR. Simulation results show that modifying the phase of the OFDM before applying the technique reduces the number of the sub-blocks for the same amount of PAPR reduction

Critical perspective on consumer animosity amid Russia-Ukraine war

Peer reviewedPostprin

Energy harvesting network with wireless distributed computing

Bulky processing tasks are expected to burden the limited resources of energy harvesters by draining the stored energy, and thereby, reaching rapidly to energy causality constraint. In such scenario, energy harvesters flip into sleep mode, and thereby, the execution time of the next task will be delayed until the energy harvesters revert back into active mode. To tackle this problem, this paper proposes a novel energy harvesting network (EHN) that deploys wireless distributed computing (WDC) network within the decision making process (DMP). The DMP is formulated as constrained partially observable Markov decision process in order to enable the energy harvesters to act under uncertainty. Furthermore, various challenges of WDC networks, e.g., nominating the collaborating nodes and task allocation, have been addressed herein. Unlike conventional research works on WDC networks, a system model is proposed for WDC network based on divisible load theory instead of graph theory. In addition, an adaptive task allocation algorithm is proposed to distribute the task efficiently among the collaborating nodes. Finally, the novel EHN system is analyzed and compared against the conventional research works on WDC, offloading computing, and local computing-EHN, where the proposed system is found to outperform in terms of energy and delay

Numerical investigation of semiempirical relations representing the local Nusselt number magnitude of a pin fin heat sink

Heat transfer augmentation study using air jet impingement has recently attained great interest toward electronic packaging systems and material processing industries. The present study aims at developing a nondimensional semiempirical relation, which represents the cooling rate (Nu) in terms of different geometric and impinging parameters. The spacing of the fin (S/dp) and the fin heights (H/dp) are the geometric parameters, while the impinging Reynolds number (Re) and nozzle‐target spacing (Z/d) are the impinging parameters. During the plot of the Nusselt profile, three vital secondary peaks are observed due to local turbulence of air over the heat sink. To incorporate this nonlinear behavior of the Nusselt profile in developing nondimensional empirical relations, the Nusselt profiles are divided into different regions of secondary rise and fall. Four different sets of the semiempirical relation using regression analysis are proposed for Z/d ≤ 6, H/dp ≤ 4.8 with S/dp ≤ 1.58, S/dp > 1.58 and for Z/d > 6, H/dp > 4.8 with S/dp ≤ 1.58, S/dp > 1.58. These empirical relations benefit the evaluation of the cooling rate (Nu) without any experimentation or simulation