A class of applications, such as home energy management and control and utility data acquisition, is emerging in recent times where smart meters, sensors, and appliances are networked together for intelligent management and coordination. Such applications rely on low data rate communication of monitoring and control information at large scale. For the underlying networking infrastructure to facilitate communication of the real-time and intermittent packet traffic expected, random access-based protocols are regarded as suitable medium access control solutions. A key challenge in this regard is that the random access protocols are prone to throughput degradation when the number of contending nodes grows, as expected with the infrastructures involved. Besides, provision for certain degree of criticality/priority is needed for some of the packets compared with the rest. With this background, this paper analytically determines the criterion for throughput-optimal operations in a network based on low-rate carrier sense multiple access protocol. In addition, ways to provide priority-wise access differentiation at arbitrary proportions without a negative impact on the achievable throughput is incorporated within a binary exponential backoff -based collision avoidance scheme. Discrete-event simulations are performed to validate the accuracy of the approximations made in analysis.sensor-driven and actuator-driven home automation systems, coordinating intelligent energy management decisions for the appliances at the consumers' end [9], related applications spanning across neighborhoods [10], and even cities [11]. A critical enabling element in this regard is the last-mile network access technologies of the future smart grid communication systems encompassing homes, buildings, and neighborhood.Accordingly, recent years have seen significant efforts to devise the technologies that make efficient communication of the associated monitoring data and control information possible [12]. Aside from the many network layer solutions proposed in the literature [13], standardization efforts are under way at the Internet Engineering Task Force toward adaptation of the IPv6 routing protocol for low-power and lossy networks in line with the requirements pertaining to home/building area networks and communication infrastructure for metering data management [14]. At the physical layer, notable developments have taken place with two technologies: a) narrowband powerline communication (PLC) solutions represented by the technical specifications from the PRIME (Pow-eRline Intelligent Metering Evolution), G3-PLC and HomePlug alliances, as well as in the recently released IEEE 1901.2 standard; and b) wireless-based solutions, with a key representation in the IEEE 802.15.4g standard with the physical layer amendment from the task group 4g for smart utility networks.The scope of this paper is within the medium access control (MAC) layer. As many of the relevant applications are poised to deal with real-time traffic and event-driven communications, r...
