Low power wide area (LPWA) technologies are strongly recommended as the underlying networks for Internet of things (IoT) applications. They offer attractive features, including wide-range coverage, long battery life and low data rates. This paper reviews the current trends in this technology, with an emphasis on the services it provides and the challenges it faces. The industrial paradigms for LPWA implementation are presented. Compared with other work in the field, this survey focuses on the need for integration among different LPWA technologies and recommends the appropriate LPWA solutions for a wide range of IoT application and service use-cases. Opportunities created by these technologies in the market are also analyzed. The latest research efforts to investigate and improve the operation of LPWA networks are also compared and classified to enable researchers to quickly get up to speed on the current status of this technology. Finally, challenges facing LPWA are identified and directions for future research are recommended.

Abstract-With the inevitable dominance of video traffic on the Internet, providing perceptually good video quality is becoming a challenging task. This is partly due to the bursty nature of video traffic, changing network conditions and limitations of network transport protocols. This growth of video traffic has made Quality of Experience (QoE) of the end user the focus of the research community. In contrast, Internet service providers are concerned about maximizing revenue by accepting as many sessions as possible, as long as customers remain satisfied. However, there is still no entirely satisfactory admission algorithm for flows with variable rate. The trade-off between the number of sessions and perceived QoE can be optimized by exploiting the bursty nature of video traffic. This paper proposes a novel algorithm to determine the upper limit of the aggregate video rate that can exceed the available bandwidth without degrading the QoE of accepted video sessions. A parameter β that defines the exceedable limit is defined. The proposed algorithm results in accepting more sessions without compromising the QoE of ongoing video sessions. Thus it contributes to the optimization of the QoE-Session trade-off in support of the expected growth of video traffic on the Internet.

<div>Low-power wide area (LPWA) technologies are strongly recommended as the underlying</div><div>networks for Internet of Things (IoT) applications. They offer attractive features, including wide-range</div><div>coverage, long battery life, and low data rates. This paper reviews the current trends in this technology,</div><div>with an emphasis on the services it provides and the challenges it faces. The industrial paradigms for LPWA</div><div>implementation are presented. Compared with other work in the field, this paper focuses on the need for</div><div>integration among different LPWA technologies and recommends the appropriate LPWA solutions for a</div><div>wide range of IoT application and service use cases. Opportunities created by these technologies in the</div><div>market are also analyzed. The latest research efforts to investigate and improve the operation of LPWA</div><div>networks are also compared and classified to enable researchers to quickly get up to speed on the current</div><div>status of this technology. Finally, challenges facing LPWA are identified and directions for future research</div><div>are recommended.</div>

This letter studies the performance of a single gateway LoRa system in the presence of different interference considering the imperfect orthogonality effect. It utilizes concepts of stochastic geometry to present a low-complexity approximate closed-form model for computing the success and coverage probabilities under these challenging conditions. Monte Carlo simulation results have shown that LoRa is not as theoretically described as a technology that can cover few to ten kilometers. It was found that in the presence of the combination of signal-to-noise ratio (SNR) and imperfect orthogonality between spreading factors (SF), the performance degrades dramatically beyond a couple of kilometers. However, better performance is observed when perfect orthogonality is considered and SNR is not included. Furthermore, the performance is annulus dependent and slightly improves at the border of the deployment cell annuli. Finally, the coverage probability declines exponentially as the average number of end devices grows.