## 5 Implemented Scenarios and Experimental Results
* IPsec (VTI, XFRMi, Classic): ensures secure communications with optimized encryption and tunneling techniques. * Tinc and Nebula: offer mesh networking solutions that scale efficiently while maintaining security. Proxmox VE enhances CPU management through various techniques to ensure that virtual machines (VMs) and containers run efficiently:

* KVM (Kernel-based Virtual Machine): utilizes hardware virtualization extensions (Intel VT-x and AMD-V) to ensure near-native performance for VMs. * CPU Pinning: allows binding of VMs to specific CPU cores, reducing context switching and optimizing performance. * NUMA (Non-Uniform Memory Access) Awareness: Proxmox can optimize memory and CPU allocation across NUMA nodes, improving access times and overall VM performance. * Resource Limits and Quotas: enable setting limits and quotas for CPU usage, ensuring fair distribution of resources and preventing any single VM from monopolizing CPU resources. * Dynamic Resource Allocation: Proxmox dynamically adjusts resources based on current workload demands, optimizing CPU and memory usage. * CPU Hotplug: allows adding CPUs to running VMs without downtime, providing flexibility and scalability. * Integration with cgroups and namespaces: ensures fine-grained control over resource allocation and container isolation, optimizing CPU usage. Proxmox VE's optimizations in network and CPU management layers ensure that virtualized environments operate with high efficiency and performance. The comprehensive support for advanced networking technologies combined with robust CPU management techniques makes Proxmox VE a powerful platform for modern data centers and cloud environments. Conceptualization, A.F.G., P.F. and D.M. ; methodology, E.G. ; software, A.F.G. ; validation, A.F.G., D.M. and E.G. ; data curation, A.F.G. and P.F. ; writing--original draft preparation, A.F.G. and P.F. ; writing--review and editing, A.F.G. and P.F. ; supervision, A.F.G. All authors have read and agreed to the published version of the manuscript. The research by P.F. leading to a part of the published results was supported by the European Union within the REFRESH project - Research Excellence For Region Sustainability and High-tech Industries ID No. CZ.10.03.01/00/22 003/0000048 of the European Just Transition Fund. Data Availability Statement: The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author. ## Conflicts of Interest: The authors declare no conflicts of interest. ## Abbreviations

The following abbreviations are used in this manuscript: \begin{tabular}{l l} AES & Advanced Encryption Standard \\ AH & Authentication Header \\ EAP & Extensible Authentication Protocol \\ ESP & Encapsulating Security Payload \\ GDPR & General Data Protection Regulation \\ HW & Hardware \\ IETF & Internet Engineering Task Force \\ IKE & Internet Key Exchange \\ IoT & Internet of Things \\ IPsec & IP Security \\ ISAKMP & Internet Security Association and Key Management Protocol \\ MQTT & Message Queue Telemetry Transport \\ NAT & Network Address Translation \\ OTP & On-Time Password \\ PSK & Pre Shared Key \\ PSTN & Public Switched Telephone Network \\ RTT & Round Trip Time \\ RW & Road Warriors \\ SAD & Security Association Database \\ SPD & Security Policy Database \\ SSL & Secure Sockets Layer \\ SW & Software \\ TLS & Transport Layer Security \\ UTP & Unshielded Twisted Pair \\ VPN & Virtual Private Network \\ \end{tabular} 

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