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The dynamic development of multiservice cellular networks has resulted in significant changes in the system architecture, which, in turn, has led to a broad distribution of many mechanisms and functions responsible for traffic management. These mechanisms take advantage of appropriate algorithms and analytic dependencies to ensure optimal quality of service that can be tailored to the objectives of the network operator. This paper proposes a new analytical model of a cellular network that supports multicast connections in a distributed environment. It is assumed that, in the cells participating in multicast connections, it is possible to apply different and independent traffic management mechanisms such as, for example, threshold mechanisms and resource reservation mechanisms. The proposed method can be used in an evaluation and scientific methods of research in the traffic effectiveness of multicast connections in given load conditions of a cellular network. An application of the method can have a particular significance in designing high-bit-rate multicast services to users in 4G networks. The analytical model proposed in this paper is verified on the basis of simulation examinations of cellular networks with multicast connections. The investigations confirm high accuracy of the model and the correctness of all theoretical assumptions adopted in the study.

The planning of metering network infrastructure based on the concept of the Internet of Things primarily involves the choice of available radio technology. Then, regardless of the type and availability of power sources, energy conservation should be one of the main optimization criteria. For this reason, LPWANs operating in unlicensed ISM bands appear to be a suitable solution in urban environments due to their sub 1 GHz propagation properties. High signal penetration and coverage make them applicable in urban areas with buildings and various obstacles. Therefore, this article presents solutions developed to support the planning process of implementing a LoRaWAN network infrastructure aimed at monitoring and collecting electricity meter data in smart cities. To this end, an algorithm has been proposed to support the selection of the number of LoRaWAN gateways and their deployment, as well as the selection of transmission parameters at the measurement nodes with a particular focus on geographic data from real maps.

Limited resources in Wireless Sensor Networks (WSNs) are the key concern that needs to be given a careful consideration when studying virtually any aspect of a sensor network. Therefore, energy demands and radio bandwidth utilization should be addressed, especially in one-to-many communication. To define the problem, this article presents and categorizes the most common WSN multicast procedures depending on the way a target group is identified by the means of geographic position. It is evident that a need for centralized network-wide topology knowledge can jeopardize scarce energy resources of a sensor network. Thus, localized geographic multicast relies solely on locally available information about the position of current node, other nodes within the radio range and the location of destination group members. Greedy multicast routing procedures often transport messages along paths that may be far from being optimal. Therefore, Dijkstra-based Localized Energy-Efficient Multicast Algorithm (DLEMA) is introduced. DLEMA focuses on discovering energy shortest paths leading through nodes that provide maximum geographical advance towards desired destinations. The analysis of the simulation results confirms interesting characteristics of the proposed algorithm.