## 4 Network Requirements for Smart Microgrids  
To control and monitor the intelligent microgrid, a Real-Time Measurement Parameters (RTMP) function is required [69; 70]. To reach this objective, it is mandatory to know what bandwidth (used to signify the data rate in bits/second) and what latency (delay) the transmitted data may have among the microgrid components (DERs) for each microgrid function [71; 72; 73]. Each microgrid function has its own latency and bandwidth requirements depending upon the kind of system response it is dealing with. The International Electrotechnical Commission's (IEC) 61850 and IEEE 1646 standards give specifications for these requirements as Table 1 summarizes [74; 75; 76]. The communication system of the microgrid must satisfy these timing requirements because a low bandwidth can lead to bottlenecks, loss of data packets and distortion. Besides, if the communication delay exceeds the required time, the information does not fulfill its purpose and, in the worst case, damage might occur [34]. In this regard, the underlying communication system needs to be designed with well-defined network performance requirements to meet the needs of time sensitive data streams, bandwidth and latency, among others [77; 78]. Table 1 shows the needed performance requirements as stated by the IEC 61850 and IEEE 1646 standards. Besides these requirements, microgrids are evolving towards distributed and intelligent systems, needed to process a high volume of data. Thus, the management and control of microgrids is becoming a critical challenge. The latest research indicates that current distributed MAS have some limitations for the efficient and optimal management of microgrids [49; 79; 80; 81; 82]. On the one hand, to get the overall information about the microgrid dynamic network, the agents should be grouped in clusters, following a certain criterion (for instance, the kind of resource). The absence \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Application**} & \multicolumn{2}{c}{**Network Requirements**} \\ \cline{2-3}  & **Bandwidth** & **Latency** \\ \hline Demand response & 14–100 Kbps & 500 ms–several minutes \\ Distributed energy resources and storage & 9.6–56 Kbps & 20 ms–15 s \\ Distributed management & 9.6–100 Kbps & 100 ms–2 s \\ \hline \hline \end{tabular}
\end{table} 
Table 1: MG application and network requirement as stated by IEC 61850 and IEEE 1646 standards. of such functionality might result in a lack of knowledge about the global status of the microgrid and, therefore, in sub-optimal resource allocation. On the other hand, agents have neither dynamic reorganization nor self-healing capabilities by themselves, which would result in better response to local-failures, microgrid blackouts, agents' crashes or communication failures. According to the general needs described above, P2P communication systems offer some interesting features to meet the desired requirements. First, P2P protocols have a high degree of flexibility and can be easily adapted to new applications by means of overlays. Second, the communication system must be highly scalable while maintaining the capability to process the growing volume of data. These characteristics are inherent to P2P systems. However, P2P networks were mainly developed for file sharing and processor cycle sharing. In these applications, the network performance requirements are less critical than the ones of microgrids (see Table 1). Thus, they should be adapted to provide:  
1. An application layer to retrieve data from the system. In conventional DHTs, the nodes store the keys to locate information of the key it is responsible for. Thus, each node should establish its own methods to retrieve this information. To achieve this objective a communication infrastructure based on a stack protocol with an application layer has to be developed according to the goals of the microgrid. 2.