2019 IEEE Symposium on Computers and Communications (ISCC) Leveraging Mobile Edge Computing on Smart Grids Using LTE Cellular Networks Alex F R Trajano∗ , Antonio Alex Monteiro de Sousa† , Emanuel B Rodrigues‡ , José Neuman de Souza§ , Arthur de Castro Calladok and Emanuel F Coutinho∗∗ Instituto Atlântico - Fortaleza - Brazil Universidade Federal do Ceará - Fortaleza - Brazil Email: ∗ alex_ferreira@atlantico.com.br, † alex_sousa@atlantico.com.br, ‡ emanuel@dc.ufc.br, § neuman@ufc.br, k arthur@ufc.br, and ∗∗ emanuel.coutinho@ufc.br Abstract—Given the advance of the Smart Grid technology, the electrical grid is now in a process of transformation never seen in history. This new grid model allows customers and providers to generate and manage electrical power efficiently. To support such transformation, a key element of the model is the communication network responsible for delivering measurement data from sensors on the grid to the applications that analyze and adapt distribution according to demands. This work proposes and evaluates a system architecture that copes with reliability and latency demands that are of much importance for a successful Smart Grid deployment, also considering the internal design of distributed applications in the context of Smart Grids. The architecture adopts a Mobile Edge Computing based infrastructure that is suitable for 4G and 5G mobile cellular networks. Experiments made on NS-3 shows that the proposed system architecture is capable of handling a realistic number of smart meters while providing low latency and network reliability, supporting many use cases of a Smart Grid deployment. I. I NTRODUCTION Smart Grid (SG) is a new generation of electric power generation, transmission and distribution system that has emerged with the purpose of making more efficient management of electrical resources. It presents features unseen in the traditional systems, such as two-way communications, real-time monitoring, self-healing and generalized control [1]. Several countries that are investing in renewable and clean energy see SG as an essential paradigm that allows a more efficient way to implement it and some of these countries are also investing in SG programs, initiatives and research. Despite the benefits of using SG and its accelerated adoption, some barriers have been found, especially the high cost of implementation. There are some challenges in the adoption of SG such as the requirement of processing large amounts of data generated by numerous smart meters. A smart meter is a device responsible for measuring several data from the electrical network of a house, business or industry, sending the data to a Meter Data Management System (MDMS) that is commonly under the infrastructure of the electrical distribution company. All the data stored at the MDMS can be used for extracting near real-time data about customer billing, distribution efficiency, electricity quality and other parameters [2]. Thus, it requires a robust infrastructure with storage, processing and networking resources, capable to cope with the demands. According to Brazilian Institute of Geography and Statistics (IBGE), Rio de Janeiro, the second largest Brazilian city, has around 5.2 million houses connected to the power grid, thus if each house has a smart meter, the amount of data exchanged in the infrastructure is high even with communication at low rates. It would be possible to consider the smart meter a type of Internet of Things (IoT) enabled device that can behave as a sensor and actuator simultaneously. Furthermore, it is also known by the electrical industry that a robust SG deployment must also provide a communication network with the lowest latency and the highest reliability possible. That is a key feature from the SG because it may improve the electrical network levels of efficiency by being aware of events as soon as they happen. For instance, if the SG communication network is able to provide low latency, it enables the fast detection of short anomaly events, allowing the distribution companies to adjust the supply chain accordingly, helping to save energy, prevent outages and complying to legal requirements regarding the energy quality. That also enables use cases related to self-healing, load balancing and critical alert notifications [3]. These features are important for efficient management of the electricity system and contribute to the clean and renewable energy policies that countries want to develop to create a clean and sustainable environment. On the other hand, Mobile Edge Computing (MEC) is an emerging and promising technology that provides an environment in which Cloud Computing resources and capabilities are placed at the edge of a mobile network, operating within the Radio Access Network (RAN), much closer to devices and end users. MEC is a new technology which is currently being standardized by the European Telecommunications Standards Institute (ETSI) [4]. Due to the fact that it is within the RAN, the users’ experienced latency tends to be dramatically reduced given the fact that the resources being consumed are much closer than it would be if it was in a traditional data center. Moreover, the shortest the distance between users and resources, the better the reliability of certain services, since the number of points of failure tends to be lower. To that extent, MEC is envisioned as one of the key technologies for 5G cellular networks, even though it could also be applied to 4G cellular networks, once it is more related to the management of resources than the RAN itself [4]. Considering the challenges of the implementation of SG and 978-1-7281-2999-0/19/$31.00 ©2019 Authorized licensed use limited to: UNIVERSIDADE DEIEEE SAO PAULO. Downloaded on February 26,2021 at 00:58:31 UTC from IEEE Xplore. Restrictions apply. 2019 IEEE Symposium on Computers and Communications (ISCC) the potential of MEC, this work approaches the challenge of obtaining a low latency and reliable communication network to support a large amount of data generated by thousands of smart meters in realistic SG deployments. The architecture leverages MEC to provide SG application services at the mobile edge on a Long Term Evolution (LTE) cellular network. The rest of the paper is structured as follows. Section II presents the related work. Section III introduces basic concepts around SG and MEC. Section IV presents the proposed architecture. Section V shows the experimental results and in Section VI presents conclusions and ideas for future work. the proposal is compelling. However, the scheme proposed by the authors is only addressed to the intelligent transport system applied on a road while our proposal is a generic architecture that addresses broader deployments. In summary, this work has the following topics as the main contributions to the field: • • • II. R ELATED W ORK In the literature, there are some works related to the use of Edge Computing applied to SG to solve problems related to processing a large amount of data generated by smart meters and improve latency. They are described next. In [5], authors suggest the adoption of MEC for communication networks, exploring the impact of MEC on the delay of messages, response time and transfer rate to handle a large amount of data generated in a specific SG environment. In this work, MEC is suggested along with vehicular delaytolerant networks to transfer and to process this large volume of data. As results obtained from the executed experiments, there were improvements in the performance, response time and in the delay. However, this work was limited only to solving problems inherent to electric vehicles only, not being a generic solution and that could cover the different complex cases existing in a SG environment. Our proposal presents a more generic solution that can be applied to different use cases, however, our architecture may not be suitable for rural areas due to poor mobile network coverage in these areas. The authors in [6] present Fog Computing as a model to be applied in SG to handle a large mass of data processing and also provide a low latency network. The authors presented a scenario and concluded that due to the geographical distribution of the model, it is possible to obtain a low latency and other benefits provided by the technology. In this scenario, a three-layer architecture is proposed, in which the first layer is formed by the smart meters that are responsible for collecting data and communicating with other devices. The second layer consists of fog servers that have the responsibility of performing processing and connecting smart meters to the cloud. The last layer consists of a cloud server that aggregates and stores data. This work is a strong candidate to optimize SG, however, no satisfactory experiments were made to assess the performance of the proposed solution. In this paper, we present the results of our experiments to show that our proposal offers a low latency environment for SG deployments. Energy efficiency and low latency for IoT applications were the focus of another work [7]. A mobility-aware hierarchical framework using a cellular network is proposed, in which MEC is composed of two layers with MEC servers. When the first tier servers are overloaded, they can unload their jobs to the second layer that has a backup server. The experiments returned good results in relation to the latency, showing that A solution that provides a network that copes with SG low latency and reliability requirements. A generic architecture that could also be applicable to other IoT applications with similar requirements to SG. Simulation experiments to assess the proposal performance considering realistic parameters and environment. III. BACKGROUND A. Smart Grid Smart Grid is a new paradigm for electric power systems that use Information and Communications Technologies (ICT) for efficient, reliable and flexible management in the generation and distribution of electricity [8]. There are three key aspects that define a SG: • • • Distribution and transmission systems that provide transparency and control of their resources. Renewable sources of energy, distributed energy generation and power storage on both sides of the meters. The capacity to dynamically respond to demand. In order to achieve these three key aspects, SG relies on ICT to integrate the management systems and the electric infrastructure in an automatized way. To do so, it includes the utilization of sensors and actuators at the power lines and on consumer premises, along with a reliable two-way communication infrastructure with wide coverage for the devices. These devices usually communicate with the MDMS, performing real-time monitoring of the network and adjusting the energy production and distribution according to the current demands. Smart meters, as shown in Figure 1, are intelligent devices installed at the houses of end consumers that collect realtime measurement data and enable remote operations, making management of the electrical system efficient. These data often include the amount of consumed energy, the current voltage and amperage, and many other parameters [9]. Communication from smart meters to MDMS can be done with different wired or wireless network technologies data [10]. Certain SG functionalities require low latency and reliability [1], such as real-time monitoring for efficient management of power generation and distribution, energy balancing, sending of alerts and handling of failures. With the emergence of IoT, various devices and sensors act on the network collecting data and triggering events for the automation of different activities without human intervention [11]. As mentioned earlier, smart meters are smart devices that take measurements and can also behave like actuators, so we can see them as IoT devices. Low latency is also seen as an important requirement for certain functionalities in the IoT environment [12]. Based on this, we can say that low latency Authorized licensed use limited to: UNIVERSIDADE DE SAO PAULO. Downloaded on February 26,2021 at 00:58:31 UTC from IEEE Xplore. Restrictions apply. 2019 IEEE Symposium on Computers and Communications (ISCC) Aggregator MDMS Wide Area Network Aggregator Figure 1. SG deployment scenario for electrical energy distribution for residencies. A communication network must be able to measure data coming directly from smart meters installed at each house and aggregator devices. in SG would be a subproblem of IoT and that our proposal may also benefit other IoT applications. The latency requirements for some SG critical application use cases such as Distribution Automation, Wide-Area Situational Awareness and Substation Automation lies between 20 and 200 milliseconds, while other use cases do not have any latency requirement [2]. Not surprisingly, critical SG use cases also require network reliability, which means that no losses should be admitted. The work [13] presents some communication technologies that could be used by SG along with their expected latency, showing that supporting the critical use cases is a challenging task to accomplish. Figure 2. Overall organizational view of MEC components in a LTE mobile cellular network [17]. The MEC server directly connected to the eNodeB guarantees the latency improvement to UEs due to the shorter distance when compared to the traditional data centers. 5G is being developed with significant features to meet the high consumer demand imposed by the increase in the number of connected devices that according to Gartner it will reach 20.4 billion devices by 2020. For both 4G and 5G optimization, other technologies such as Network Functions Virtualization (NFV) and Network Slicing can be used. Network Slicing allows custom and isolated network structures to be delivered to specific groups of devices or end users [18], while NFV allows the implementation of multiple Virtualized Network Functions (VNFs) over a common physical network [19], making it a great tool for the construction of these network slices. These technologies could also leverage the use of MEC since different services can be offered to different groups of end users. In the case of a SG scenario, a specific network slice could be offered to meet the needs of the electricity sector. B. Mobile Edge Computing in Cellular Networks MEC is an emerging technology that enables features found in cloud computing and in edge computing [14]. MEC works within the RAN [15] and due to the adoption of edge computing, it allows offering services closer to mobile devices and end users. There is another technology similar to MEC, known as Fog Computing, that also offers services close to end users. However, Fog computing performs processing on a Fog node or in an IoT gateway within a Local Area Network (LAN), while MEC performs the processing on servers that are within a RAN [16]. Figure 2 presents a brief description of how a MEC server is placed in the mobile network, providing low latency to User Equipments (UEs). Since MEC operates within a RAN, mobile telecommunication technologies can be used. The widespread 4G already achieves good bandwidth rates, while the incoming 5G will allow much higher ones, thus making MEC a very good option when high bandwidth rates are required. Therefore, MEC is an excellent alternative to meet the low latency requirement of SG due to the proximity of resources offered by the edge. The use of edge servers in mobile networks can also be useful for Narrowband Internet of Things (NB-IoT), which has also been suggested as an option to support SG networking, even not supporting low latency requirements of some common SG use cases [13]. IV. P ROPOSED S YSTEM A RCHITECTURE This work proposes a system architecture that builds a reliable communication network to be used in a SG deployment. As mentioned earlier, SG needs a network capable of delivering messages with low latency in the widest coverage possible, since smart meter devices span a whole city. Given these requirements, this work proposes the use of a mobile cellular network of 4th or 5th generation. That seems to be a good approach because cellular networks evolve in a fast pace, and it is envisioned that 5th generation networks will be able to give better support for numerous IoT devices. Although 5th generation cellular networks are envisioned to be an important enabler for supporting a large number of IoT devices, SG can be extended to support 4th generation cellular networks as well, by adopting MEC on existing LTE infrastructure. This way, Mobile Network Operators (MNOs) can provide support for future SG deployments, which in turn could benefit from the advantages of using a cellular network, as discussed in Subsection IV-A. The proposed architecture is presented in Figure 3. It consists of a MEC architecture in which the servers are allocated in base stations, where each base station covers a certain geographic perimeter with a number of houses. Each house has a smart meter that performs bidirectional communications Authorized licensed use limited to: UNIVERSIDADE DE SAO PAULO. Downloaded on February 26,2021 at 00:58:31 UTC from IEEE Xplore. Restrictions apply. 2019 IEEE Symposium on Computers and Communications (ISCC) with MEC through wireless cellular communication. Edge servers can communicate with a cloud over a wired or wireless network so measurement data can be sent to MDMS. In addition, data transmitted to MEC can be stored at the edge, making it available to users if needed. tion interfaces to receive and send data. In this illustration, application A in MEC Server A can communicate with the cloud through the cloud interface, with smart meters through the meter interface and with another application A in MEC Server B through the side interface. MDMS MEC Server A MEC Server B Cloud Interface Smart Meter Cloud Smart Grid Application A Side Interface Side Interface Smart Grid Application A Smart Meter Smart Meter Aggregator Cloud Interface Smart Meter DB SG Application DB SG Application Smart Meter Meters Interface Meters Interface Cloud Interface Cloud Interface Aggregator Smart Grid Application B Side Interface Side Interface Smart Grid Application B Smart Meter MEC Server MEC Server Meters Interface Smart Meter Meters Interface Smart Meter Figure 4. The internal design of a SG application on a MEC server. Device Sensor Sensor Device Figure 3. Overview of the proposed SG communication network using MEC servers in a cellular network infrastructure. Smart meters measurement data flow to the applications within MEC servers, which in turn can be sent over the cloud heading the MDMS. In addition to intelligent meters, other devices, such as measurement sensors, actuators, and even devices manipulated by authorized users, can interact with services that can run on the MEC. There are some examples of devices that connect to the SG that would benefit from the proposed architecture: • Smart meters can transmit measurement data with realtime measurement records, as well as trigger alarms and events that can be transmitted to the MEC for storing and processing data, as well as handling events or sending notifications; • Measuring sensors and actuators can collect light measurement data and transmit this data to the MEC that can store and/or process the collected data making public lighting management more efficient. In the proposed architecture, applications are deployed in MEC servers within the MNO infrastructure, which means a new type of business for the MNOs, which can bill the electrical distribution companies that use their resources. Besides, SG traffic would be handled in the same infrastructure that also supports traditional mobile users, which may incur in a huge overload of the network. Fortunately, MNOs can rely on Network Slicing to make sure business needs can be met by the virtual separation of resources in the mobile network. Figure 4 shows the internal design of applications that can run on edge servers and their communication interfaces. Servers can run one or more applications that can communicate with smart meters or other devices, with the cloud or with each other. The figure shows two servers, where each server is running both applications, A and B, and applications can execute specific processes and have specific communica- The need for a side interface in applications is to allow the development of more complex distributed applications that may be used to offload the MDMS servers. There are situations in which problems in the electrical network can be solved locally. For instance, consider a neighborhood that is facing minor power surges due to some local event that happened shortly. In such example, applications in MEC servers can directly connect to the neighborhood’s distribution substation and notify the distribution controllers to change its parameters accordingly so problems can be repaired in a much shorter time than it would be by the MDMS. This way, applications can communicate between themselves within the mobile cellular network using the side interface, which is the basis for supporting distributed systems on the MEC layer. Applications deployed in such infrastructure should be designed with the same principles that are commonly used in cloud environments, including provisioning, elasticity and some software architectural patterns like microservices. That is one of the reasons that a side interface is needed since it is an enabler for such cloud computing techniques. A. Advantages of Using the Proposed Architecture The architecture presents some advantages that justify its adoption to enhance the electrical system management in SG. 1) Low latency: With MEC, services are available near devices and users, thus achieving low latency [20]. In the power sector, it is important to achieve low latency for certain features, such as power balancing, real-time monitoring, fault handling, alerts, and self-healing [2]. 2) Coverage of the mobile network in urban centers: The existing mobile network infrastructure provided by telecommunication companies allows the implementation of the proposed architecture with a wide coverage area since cellular networks typically cover most or all of the urban areas. Moreover, good coverage also minimizes network outage problems, Authorized licensed use limited to: UNIVERSIDADE DE SAO PAULO. Downloaded on February 26,2021 at 00:58:31 UTC from IEEE Xplore. Restrictions apply. 2019 IEEE Symposium on Computers and Communications (ISCC) which increases availability and provides better support for delivering critical events detected on the SG. 3) Costs: Capital Expenditure (CAPEX) and Operational Expenditure (OPEX) can be reduced in electric and telecommunication companies. Since energy companies can use the existing telecommunications infrastructure, commercial contracts with telecommunications companies can be signed; this way, the CAPEX for the implementation of the infrastructure is reduced. Likewise, OPEX can be reduced, since the maintenance of the infrastructure of the telecommunication networks would be done by the suppliers of the mobile technology solutions. Another positive factor is that companies in the electric sector that use SG for power management could benefit from the optimization offered by the proposed architecture, and thus may increase operational performance and reduce costs with maintenance teams. Telecommunication companies could also benefit from being able to sign contracts for infrastructure services and the use of the mobile services they can provide, as well as the possibility of signing an agreement with the electric companies that can reduce power consumption costs. B. Disadvantages of Using the Proposed Architecture 1) SLA, QoS and Concurrency: Telecommunication companies offer services to mobile end users, generating a share of resources. By sharing telecommunication resources with many other users, concurrency may become a problem to be handled by the telecommunication companies on periods of high demand. QoS could be affected since once the data throughput is not at acceptable levels, low latency is not reached and communication can disrupt. In addition, due to its novelty, it is still uncertain how the commercial agreements between energy companies and telecommunications companies would be. Network Slicing [21] is an alternative for this case since specific infrastructures can be made available to serve different groups of users, ensuring service availability and good QoS levels. 2) Coverage of the mobile network in rural areas: In some rural areas, mobile network coverage is poor, which would make the adoption of this architecture impracticable there. Other communication techniques should be applied in this scenario, since it may not be economically advantageous to install the cellular network infrastructure needed to support MEC in distant rural areas. 3) Costs: To use the mobile network features proposed in this architecture, telecommunication companies must have an infrastructure capable of supporting MEC servers at base stations. Since MEC is still an emerging concept, telecommunication companies may have to invest in upgrading their infrastructure to support MEC. V. P ERFORMANCE E VALUATION In order to evaluate the use of a cellular mobile network to support SG demands, a simulation was designed to assess if the network is able to support a large number of SG devices. In the simulation, a 4th generation LTE infrastructure was used to support a varying number of smart meters in a topology extracted from an actual LTE deployment of a neighborhood in the city of Fortaleza, Brazil. Figure 5 shows the base stations locations in a map. Figure 5. Google Maps view of Fátima neighborhood used in the simulation. All LTE base stations are represented by the antenna icons, while the blue spot represents the approximate center location in the neighborhood area. A. Simulation Environment The NS-3 version 3.28 has been used to implement the experiments due to its native LTE module, which has good support for LTE-based simulations. A machine with an Intel Xeon E5-2670 processor with 8 cores and 24GB of memory has been used. Simulations were repeated 30 times in order to present results following the Central Limit Theorem. The entire experiment took 10 hours to finish. The LTE base stations and the smart meter LTE devices used the NS3 ConstantPositionMobilityModel with fixed positions. The coordinates for the LTE base stations were obtained from actual base stations deployed in the city, while the coordinates for the smart meters were randomly generated with at a maximum radius of 1km from the central coordinate (see Figure 5). The LTE network was configured with parameters shown in Table I, which are based on the ITU-R M.2135-1 report [22], following the urban macro-cell scenario. Table I PARAMETERS USED IN NS-3 Parameter Transmission mode Uplink bandwidth Downlink bandwidth Base station transmission power Smart meters transmission power Base station noise figure Smart meters noise figure LTE scheduler Frequency reuse algorithm Radio propagation model Antenna model Antennas orientation Antenna maximum gain SIMULATION Value MIMO Multi-User 20 MHz 20 MHz 49 dBm 24 dBm 5 dB 7 dB Proportional fair scheduler Soft frequency reuse COST-Hata-Model Cosine antenna model 0, 120 and 240 degrees 17 dB The simulation goal was to measure how a network with the following characteristics performs: Authorized licensed use limited to: UNIVERSIDADE DE SAO PAULO. Downloaded on February 26,2021 at 00:58:31 UTC from IEEE Xplore. Restrictions apply. 2019 IEEE Symposium on Computers and Communications (ISCC) Each LTE base station has a MEC server with a SGenabled application deployed and running on it. • The closest MEC server is the one directly connected to the eNodeB the smart meter is connected to. Thus, the server selection is directly affected by the LTE algorithms responsible for allocating UEs to base stations. • N smart meters are sending measurement data to their MEC server. The data is sent through UDP datagrams. • There might be aggregator devices capable of gathering data from near smart meters and sending data in batch to the closest MEC server. The number of aggregator devices is determined by the aggregation factor aF . • Each smart meter sends data in fixed intervals of 1 minute. Simulations have two variables: N , the number of smart meters that are active in the network, and aF , the aggregation factor representing the percentage of aggregation used in SG deployment. An aggregator device behaves as a gateway that receives data from near smart meters and sends it to the closest MEC server, so that aggregated smart meters no longer need to be directly connected to the cellular network. In order to establish communication between smart meters and aggregators, techniques such as Power Line Communication (PLC) could be used [8]. It is easy to notice that the larger the number of households and company buildings, the larger the value of N . The value of aF is directly related to the planning of the SG deployment. For instance, if a neighborhood is known to be more vertical than others, it means that the number of apartment blocks is higher, then it would be easy to have an aggregator per each apartment block, considerably reducing the number of devices sending data through the cellular network. That way, the aF parameter tends to be directly proportional to the population density of an area. According to the last demographic census from IBGE, the Fátima neighborhood has around 7000 homes in an area of 1186677m2 , thus with a high population density. Taking that into consideration, the simulation tried to reproduce those numbers in terms of N and aF . Figures 6 and 7 show the obtained results for the average perceived delay and jitter from the smart meters standpoint, with values of N equal to 2000, 4000, 6000, 8000 and 10000, and aF equal to 0%, 25% and 50%. A 95% confidence interval is used to calculate the error margin. The delay, jitter and loss metrics have been measured by the FlowMonitor component of NS-3, considering the amount of time needed to send data from either smart meters or the aggregator devices to the closest MEC server. Each smart meter sends UDP datagrams at random intervals between 10 and 100 milliseconds and sizes uniformly distributed between 100 and 1000 bytes. • B. Achieved Results Figure 6 shows the perceived average delay in milliseconds on the communication between the smart meters and their closest MEC server. One can notice that the aggregation factor is an important parameter to be considered when designing robust SG deployment. Depending on the delay requirements of the SG applications, a 65-millisecond delay, such as seen on the scenario with 10000 smart meters without any aggregator device, can be considered high to some SG use cases. However, introducing an aggregation factor of 25% or 50%, the delay drops to less than 40 ms or around 25 ms, respectively. Figure 6. The average delay (in milliseconds) of messages sent from a number of smart meters to their MEC server in different aggregation percentages. Figure 7 shows the perceived average jitter in milliseconds on the communication between the smart meters and their closest MEC server. One can recognize this behavior as similar to the delay results shown in Figure 6, showing how important is the aggregation factor in actual SG deployments. Figure 7. The average jitter (in milliseconds) of messages sent from a number of smart meters to their MEC server in different aggregation percentages. During the experiments, the NS-3 FlowMon component has not reported any packet loss from the data sent by smart meters to their closest MEC servers, regardless of N and aF values. Such result could be explained by the simulation settings from ITU-R and the number of base stations used in the simulation Authorized licensed use limited to: UNIVERSIDADE DE SAO PAULO. Downloaded on February 26,2021 at 00:58:31 UTC from IEEE Xplore. Restrictions apply. 2019 IEEE Symposium on Computers and Communications (ISCC) (see Figure 5), indicating that the number of simulated devices are not enough to saturate the spectrum. This suggests the LTE can be considered a reliable option for SG, at least in areas with good network coverage. VI. C ONCLUSION AND F UTURE W ORK This work presented a system architecture for a SG communication network that is capable of providing a reliable infrastructure that allows electrical energy distributors to deploy SG applications over MEC servers placed in traditional LTE mobile cellular networks. The architecture allows SG applications to run at the mobile network edge, precisely at LTE base stations, providing low latency communication to smart meters. The design also enables SG applications to run as distributed systems at the edge, which facilitates scalable applications to be developed on top of the proposed architecture. Simulation results show that the proposed system architecture is capable to deliver smart meter data with low latency and high reliability. Since latency requirements of critical use cases range from 20 to 200 milliseconds [2], it is noticeable that the aggregation factor plays a major role in the full support for such applications. By understanding the achieved results and considering the official demographic data from the Fátima neighborhood, it is perceptible that critical use cases could be supported by the underlying LTE infrastructure already deployed in the location if the smart meters rely on a 50% aggregation factor, which is a tangible value given the population density of that place. The rise of 5th generation mobile cellular network may become an important factor to consider when adopting MEC to handle SG demands. The increase in the number of antennas and the utilization of higher frequencies in the communication can benefit SG devices since there is more room for improvement on interference levels, thus reducing latency and increasing the number of users. Therefore, future work should extend experiments to use 5G protocols. Another future work is related to security. A big concern surrounding the adoption of a shared mobile network is the risk of cyber attacks, which may spy on and/or tamper with data, as well as trigger undue actions affecting the electrical system (e.g., power shutdown in a region). Finally, a neighborhood of one of the largest Brazilian cities was used as a case study to analyze the effectiveness of the proposal. In this way, future work includes an extensive analysis of demographic data from the whole country, in order to trace the different profiles that are the target of SG, helping a better and broader analysis of the obtained results. R EFERENCES [1] X. Fang, S. Misra, G. Xue, and D. Yang, “Smart grid—the new and improved power grid: A survey,” IEEE Communications Surveys & Tutorials, vol. 14, no. 4, pp. 944–980, October 2012. [2] V. C. Gungor, D. Sahin, T. Kocak, S. Ergut, C. Buccella, C. Cecati, and G. P. 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