Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 1) ZigBee <s> Video-on-demand (VOD) service requires balanced use of system resources, such as disk bandwidth and buffer, to accommodate more clients. The data retrieval size and data rates of video streams directly affect the utilization of these resources. Given the data rates which vary widely in multi-resolution video servers, we need to determine the appropriate data retrieval size to balance the buffer with the disk bandwidth. Otherwise, the server may be unable to admit new clients even though one of the resources is available for use. To address this problem, we propose the following new schemes that work together: (1) A replication scheme called Splitting Striping units by Replication (SSR). To increase the number of admitted clients, SSR defines two sizes of striping unit, which allow data to be stored on the primary and backup copies in different ways. (2) A retrieval scheduling method which combines the merits of existing SCAN and grouped sweeping scheme (GSS) algorithms to balance the buffer and disk bandwidth usage. (3) Admission control algorithms which decide whether to read data from the primary or the backup copy. The effectiveness of the proposed schemes is demonstrated through simulations. Results show that our schemes are able to cope with various workloads efficiently and thus enable the server to admit a much larger number of clients. <s> BIB001 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 1) ZigBee <s> Wireless Body Area Networks (BAN) are supposed to operate in very low transmit power regime in order to keep the Specific Absorption Rate (SAR) low. Low power transmissions are known to be very error prone. However, high reliability of communications is needed for several healthcare applications. It has been observed that the fluctuations of the Received Signal Strength (RSS) at the nodes of a BAN on a moving person show certain regularities and that the magnitude of these fluctuations are significant (5 - 20 dB). In this paper, we present BANMAC, a medium access control (MAC) protocol based on cross-layer design approach where medium access decisions are tightly integrated with physical layer conditions. BANMAC monitors and predicts the channel fluctuations and schedules transmissions opportunistically when the RSS is likely to be higher. We report the design and implementation details of BANMAC integrated with the IEEE 802.15.4 protocol stack. We present experimental data which show that the packet loss rate (PLR) of BANMAC is significantly lower as compared to that of the IEEEź802.15.4 MAC. For comparable PLR, the energy consumption of BANMAC is also significantly lower than that of the IEEEź802.15.4 MAC. <s> BIB002 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 1) ZigBee <s> Abstract The emerging IEEE 802.11ah is a promising communication standard that supports a massive number of heterogeneous devices in the Internet of Things (IoT). It provides attractive features like improved scalability, low energy consumption, and coverage of large area. In this paper, we analyze the performance of IEEE 802.11ah, and compare it with a prominent alternative, the IEEE 802.15.4. The simulation results show that the new 802.11ah standard performs better than the 802.15.4 in terms of association time, throughput, delay, and coverage range. <s> BIB003 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 1) ZigBee <s> Machine-to-Machine (M2M) communication is evolving day by day and expected to create an ecosystem of billions of electronic devices. This new class of communicating devices have very diverse traffic characteristics and pose unique challenges. The essence of this paper is to provide a survey of state-of-the-art communication technologies, architectures and development platforms, and explore their potential to support the growth of M2M applications. Thus, we review the networking techniques including wide area networks, grasping LTE, NB-IoT, EC-GSM-IoT, 5G, and other proprietary networks including SigFox, Lora, and Weightless. Furthermore the short-range capillary networks are also reviewed according to the facilities they provide for application development. Available application development protocols, cloud platforms, open source frameworks and middleware frameworks are discussed for facilitating M2M application development process. Altogether the investigation provides a broad perspective to a user for application development choices. In each section and in the end current challenges are discussed for future research work. <s> BIB004
ZigBee  is a specification designed for connecting low power wireless personal devices located in a small area. It features low data rates (a maximum of 250 kbps) and low power, which best fit applications that are delay tolerant. In addition to the low data rate, network range and capacity are two main limitations of ZigBee. ZigBee can connect up to 255 devices within a maximum of 100 m BIB004 , BIB001 . ZigBee has been widely used in WSN for a wide range of applications including home and commercial building automation, industrial plant monitoring, fitness, wellness and intensively in health and aging population care BIB002 . It has been identified as a suitable solution in agriculture and environmental monitoring BIB003 . ZigBee uses the IEEE 802.15.4 [27] medium access control (MAC) protocol for MAC layer operation BIB002 . As a low-power consumption standard, IEEE 802.15.4 is not suitable for IoT applications that require coverage of large areas and communication among a large number of devices BIB003 . Its small coverage range of 100 m and connectivity support for 255 devices can be achieved through operating in the unlicensed 2.4 GHz band using the direct sequence spread spectrum (DSSS) at data rates of as much as 250 kbps. 802.15.4 relies on the popular carriersense multiple access with collision avoidance (CSMA/CA) MAC protocol.