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collision.Figure 3 shows an operating example for the data concatenation function. Here, in the same mesh as in Fig. 2, the case is indicated that devices A, B, C, D, excluding the mesh root R, send the respective data frames to R and the frames are relayed through the route in Fig. 2 (iv). In or-dinary circumstances, it sometimes occurs that the four data frames from the radios reach R almost at the same time, and collision of frames occurs at that time and the R side cannot successfully receive them. On the other hand, in the data frame coupling function as shown in Fig. 3, for this example, one data frame combines the data frame of the same destination, and the one data frame which is relayed while combining the four data frames accordingly reaches R. erefore, performance degradation due to the collision as described above can be avoided.2.4Support for multiple servicesis function dierentiates data frames depending on the assumed applications, and the devices properly handle the respective data frames — selectively construct the routes to the mesh root.Figure 4 shows an operating example of this function. e case in this function is indicated that two mesh root devices, R1 and R2, compose respective meshes and they provide dierent services. In this case, the radios, A, B, C, and D, can join in any two meshes at the same time, and the data frames related to the respective services are relayed according to the routes on the respective meshes.3Demonstration of L2R control3.1Application demonstration of home energy management systemis subsection describes a verication example of the L2R control in NICT.Figure 5 shows the system concept of the Home Energy Management System (HEMS) to manage the home energy consumption form.HEMS is a system where a HEMS controller is con-nected to a smart meter and various home electrical appli-ances with an upper communication protocol, ECHONET Lite[9][10], visualizes power consumption and collects data from electrical appliances to control them. Among these, it is considered that the SUN radio link implements route B, the connection between the HEMS controller and the smart meter, and the HAN (Home Area Network), the connection between the HEMS controller and home elec-trical appliances. Figure 6 shows a radio application dem-onstration example to implement HAN.FiF3　Data concatenationFiF4　Support for multiple servicesFiF5　 System concept of HEMSFiF6　Radio application demonstration example to implement HAN332-5 Research and Development on the Large-Scale Mesh Management Technologies for Building-Sensing Applications