(1987). Applied Probability and Queues. Journal of the Operational Research Society: Vol. 38, No. 11, pp. 1095-1096.

https://link.springer.com/content/pdf/10.1057%2Fjors.1987.184.pdf

Applied Probability and Queues

/pdf/reversibility-and-stochastic-networks-17kl9p5ino.pdf

Reversibility and Stochastic Networks

We study a sensor node with an energy harvesting source. The generated energy can be stored in a buffer. The sensor node periodically senses a random field and generates a packet. These packets are stored in a queue and transmitted using the energy available at that time. We obtain energy management policies that are throughput optimal, i.e., the data queue stays stable for the largest possible data rate. Next we obtain energy management policies which minimize the mean delay in the queue. We also compare performance of several easily implementable sub-optimal energy management policies. A greedy policy is identified which, in low SNR regime, is throughput optimal and also minimizes mean delay.

Optimal energy management policies for energy harvesting sensor nodes

By broadcasting messages about traffic status to vehicles wirelessly, a vehicular ad hoc network (VANET) can improve traffic safety and efficiency. To guarantee secure communication in VANETs, security and privacy issues must be addressed before their deployment. The conditional privacy-preserving authentication (CPPA) scheme is suitable for solving security and privacy-preserving problems in VANETs, because it supports both mutual authentication and privacy protection simultaneously. Many identity-based CPPA schemes for VANETs using bilinear pairings have been proposed over the last few years to enhance security or to improve performance. However, it is well known that the bilinear pairing operation is one of the most complex operations in modern cryptography. To achieve better performance and reduce computational complexity of information processing in VANET, the design of a CPPA scheme for the VANET environment that does not use bilinear paring becomes a challenge. To address this challenge, we propose a CPPA scheme for VANETs that does not use bilinear paring and we demonstrate that it could supports both the mutual authentication and the privacy protection simultaneously. Our proposed CPPA scheme retains most of the benefits obtained with the previously proposed CPPA schemes. Moreover, the proposed CPPA scheme yields a better performance in terms of computation cost and communication cost making it be suitable for use by the VANET safety-related applications.

An Efficient Identity-Based Conditional Privacy-Preserving Authentication Scheme for Vehicular Ad Hoc Networks

VANet security challenges and solutions: A survey

A review: spreading factor allocation schemes for LoRaWAN

We consider a wireless sensor network with n sensor nodes. The sensed data needs to be transferred in a multi-hop fashion to a common processing center. We consider the standard data sampling/sensing scheme where the sensor nodes have a sampling process independent of the transmission scheme. In this paper, we study the problem of optimizing the end-to-end delay in a multi-hop single-sink wireless sensor network. We prove that the delay-minimization objective function is strictly convex for the entire network. We then provide a distributed optimization framework to achieve the required objective. The approach is based on distributed convex optimization and deterministic distributed algorithm without feedback control. Only local knowledge is used to update the algorithmic steps. Specifically, we formulate the objective as a network level delay minimization function where the constraints are the reception-capacity and service-rate probabilities. Using the Lagrangian dual composition method, we derive a distributed primal-dual algorithm to minimize the delay in the network.We further develop a stochastic delay control primal-dual algorithm in the presence of noisy conditions. We also present its convergence and rate of convergence. The proposal is extensively evaluated by analysis and simulations.

/pdf/distributed-algorithm-for-minimizing-delay-in-multi-hop-5010t0etmf.pdf

Distributed algorithm for minimizing delay in multi-hop wireless sensor networks

An industrial IoT network may involve hundreds of IoT end-devices deployed over large geographical wide areas networks (WAN). These devices are expected to operate over several years and their individual communication interface may be gradually upgraded with multiple communication links in order to fit the changing application and data rate requirement. As industrial networks are expected to perform with high reliability and availability, a continuous monitoring and maintenance of these communication links is essential. A software defined WAN (SD-WAN) based solution allows to adaptively monitor and manage the connectivity links as per the application requirement. In this paper we design and implement a working SD-WAN based multi-access system for upstream communication between an IoT device and the control center. Each IoT device may have multiple cellular interfaces, and we control the end-to-end delay jitter variation across the different interfaces via an intelligent traffic splitting scheme.We provide an analysis of end-to-end delay jitter under LTEs uplink connection and use the structural results so obtained to design a traffic split mechanism. We validate our analysis, and provide traffic split performance results from our working multi-access system.

Network-Coded SD-WAN in Multi-Access Systems for Delay Control

Stability and delay constraints have significant impact on the design and operation of wireless sensor networks. In this paper, we propose a closed architecture for data sampling in wireless sensor networks. Examples show that the proposed scheme outperforms the traditional layered scheme, both in terms of stable operating region as well as the end-to-end delays. We then propose a distributed routing scheme for a broad class of wireless sensor networks which converges (in the Cesaro sense) to the set of Cesaro-Wardrop equilibria. The scheme is based on multiple time-scale stochastic approximation algorithms. Convergence is established using standard results from the related literature and validated by simulation results. Our algorithm can adapt to changes in the network traffic and delays.

/pdf/a-distributed-algorithm-to-achieve-cesaro-wardrop-1jel609c56.pdf

Arzad A. Kherani

Papers

A review: spreading factor allocation schemes for LoRaWAN

Distributed algorithm for minimizing delay in multi-hop wireless sensor networks

Network-Coded SD-WAN in Multi-Access Systems for Delay Control

A Distributed Algorithm to Achieve Cesaro-Wardrop Equilibrium in Wireless Sensor Networks

Method and system for synchronizing communication between nodes in a bluetooth network