## 5 Implemented Scenarios and Experimental Results
At the same time, WireGuard and XFRMi can maintain the same performance of a clean connection. Figure 16: The trend of Tinc average RTT for different MTU lengths. Figures 19 and 20 show the connection performance for TCP and UDP connections, respectively, obtained by the _iperf_ command, with an MTU=1500B. Also, in this case, for the TCP case, there are unsuitable tunnels, such as _opencontect_, _vii_, _gre IPSec_, _vxLAN IPSec_, _xfrmi_, _IP IP IPSec_, _Gretap IPSec_, and the _clean_ connection. Then, another cluster of tunnels provides an average performance, like _vxlan_ and _Geneve_. The best results are obtained with _Geneve IPSec_, _gre_, _gretap_, _Foul_, _gue_, _IP in IP_, and _myMACVLAN_. As for the MTU = 9000B case, UDP saturates all connections for the same reasons explained in the previous case with MTU = 9000B. Figure 17: The trend of the average throughput (Mbps) for each TCP connection with only a VPN tunnel (MTU = 9000B). Figure 18: The trend of the average throughput (Mbps) for each UDP connection with only VPN tunnels (MTU = 9000B). Figures 21 and 22 show the obtained performance with the _netperf_ command for TCP and UDP tunnels, respectively, with MTU=1500B. The obtained values are comparable in the TCP case, while for the UDP case, only the _OpenConnect_ tunnel exhibits a very good throughput. Figure 19: The trend of maximum reachable bandwidth (Mbps) for each TCP connection with the underlying tunnel (MTU = 1500B). Figure 20: The trend of maximum reachable bandwidth (Mbps) for each UDP connection with the underlying tunnel (MTU = 1500B). ## 6 Conclusions and Future Works

In this work, we provided several details about VPN and Overlay connections in TCP/IP networks. In particular, we focused on analyzing several tunnels from different points of view, implementing them into virtualized environments, and giving different information on how they can be implemented. This work's second part has been dedicated to analyzing the obtainable results regarding RTT, maximum bandwidth, and throughput. One of the main results is the possibility of clustering the tunnels in the function of the reachable RTT, thus providing a wide variety of choices that respect a given RTT distribution, depending on the desired results. The second analysis that has been illustrated regards the performance of tunneling for TCP and UDP connection: we have shown how, for UDP, all the connections saturate, while for TCP, there are some preferred tunnels. The same trend has been found for the throughput analysis. Figure 21: The average reachable throughput (MBps) for each TCP connection with the underlying tunnel (MTU = 1500B). Figure 22: The average reachable throughput (MBps) for each UDP connection with the underlying tunnel (MTU = 1500B). One of the future works will certainly be to translate this study onto the Proxmox platform to evaluate the performance achievable through systems managed through this hypervisor. Proxmox VE optimizes the network and CPU management layers to deliver high performance and efficiency in virtualized environments. Here is an emphasis on these optimizations: Proxmox VE supports a wide array of advanced networking technologies crucial for creating flexible and high-performance virtual networks. These include:

* FOU (Foo Over UDP): efficient encapsulation of IP in UDP, reducing overhead. * GUE (Generic UDP Encapsulation): offers flexibility for different protocols with minimal latency. * GRE (Generic Routing Encapsulation) and GREtap: ensures robust tunneling of various network protocols and Ethernet frames, optimizing traffic flow. * IPIP (IP-in-IP): simplifies tunneling with minimal processing overhead. * GENEVE and VXLAN: provide scalable solutions for network virtualization, enhancing performance in overlay networks. * MACsec: secures data link layer communications, maintaining high throughput with encryption. * OpenVPN and WireGuard: deliver secure and efficient VPN solutions, with WireGuard specifically known for its minimal CPU usage and high performance.