## 4 Results
### Testing Scenario 2: 3D Things' Virtual Environment
Additional tests were made to assess the system's performance, in a computer characterized by the following relevant specifications:  
* Processor: 11 th Gen Intel(R) Core (TM) i7-11800H @ 2.30 GHz 2.30 GHz;
* Random Access Memory (RAM): 32 GB @ 2933 MHz SODIMM;
* Graphic Card: NVIDIA GeForce RTX 3080, 16.0 GB GDDR6 RAM (Laptop edition);
* Storage: 1 TB, 3500 MB/R, 3300 MB/W;
* Operative System: Windows 10 Home 64 Bit. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Action** & **Time (s)** & **Request** & **Output** \\ \hline Initialization & 0 & /out/D6-BB-99-92-99-3A/1/1 Off & & A \\ Initialization & 0 & /out/E1-SC-83-02-28-DD/1/1 Off & & B \\ Initialization & 0 & /out/1C-B2-89-0F-20-01/1/1 Off & & B \\ Initialization & 0 & /out/A9-94-43-C9-EB-8C/1/1 Off & & B \\ Turn on display & 1 & /out/A9-94-43-C9-EB-8C/1/1 On & & B \\ Play DC video & 1 & /out/A9-94-43-C9-EB-8C/2/1 DC & & B \\ Turn on lamp A & 1 & /out/D6-BB-99-92-99-3A/1/1 On & & B \\ Set fan rotation to 1 & 1 & /out/1C-B2-89-0F-20-01/1/1 Low & & B \\ Play Marvel Video & 30 & /out/A9-94-43-C9-EB-8C/2/1 Marvel & & B \\ Set fan rotation to 3 & 38 & /out/1C-B2-89-0F-20-01/1/1 Medium & & B \\ Turn off lamp A & 45 & /out/D6-BB-99-92-99-3A/1/1 Off & & B \\ Turn on lamp B & 45 & /out/E1-8C-83-02-28-DD/1/1 On & & B \\ Turn off lamp B & 60 & /out/E1-8C-83-02-28-DD/1/1 Off & & B \\ Turn off fan & 60 & /out/1C-B2-89-0F-20-01/1/1 Off & & B \\ Turn off display & 60 & /out/A9-94-43-C9-EB-8C/1/1 Off & & B \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Three-dimensional environment virtual devices: schedule-oriented control testing scenario. Regarding delays impacting in communications and considering that simulations run within a local host environment, MQTT publishing to subscribed topics is instantaneous (equal to or less than \(1\) ms). Moreover, substantial information on decentralized IoT-related protocols performance, several other studies--such as that found in [35]--are available. Therefore, performance tests focusing both the system's database and graphical component were carried out. Firstly, timestamp-based monitorization for registrations and updates of virtual devices states in a local Mongo database allowed to measure delays between 17-35 ms. Afterwards, graphical component tests were conducted, starting with the 2D environment, in which a set of timers were implemented to measure delays in between virtual devices state transitions. Figure 11 depicts the results, from which can be denoted a correlation between the number of states that each device may assume, and the average time required by it to consolidate a state switching. Figure 11: Two-dimensional environment performance results for each implemented virtual endpoint (lamp, fan, as well as temperature and motion sensors). Bars represent both image sizes (KB) and state switching latency (ms) per device, and the implicated axis is the left one. The line regards to the number of possible states that each device may assume, with scale in the right-hand axis. Figure 10: Three-dimensional actuators and sensors in action: the pair of lamps varying from turned off to on are represented by (**a**,**b**) regards to the fan, in idle state and during rotation; finally, in (**c**), lies the display reproducing different content. The 3D environment was also assessed in terms of performance, as shown by Figure 12, considering a couple of perspectives: (1) latency of a device while changing its state; and (2) impact of diverse displays playing content at the same time, in terms of frames per second (FPS). The left plot of Figure 12 shows the time required by the 3D endpoints to switch their state, more specifically, for lamp and fan turning representations according to their condition (power and rotation level) and for displays loading video content. Table 9 data seem to point out that video transmission features influence the computational burden during content loading, i.e., the higher the transmission rates are, the more time is needed to load a video.