Information Security (InfoSec): Definition, Principles Triad, and Threats

A hypervisor is a process that helps separate the operating system and running applications from the hardware component. This typically refers to specialized software. However, embedded hypervisors also exist. These are available from the start, rather than being launched after system deployment. The hypervisor is what enables the development of the virtualization concept. Hardware virtualization is the ability to manage multiple virtual machines (VMs) on a single device. They become guest systems. An example of virtualization in use is renting a virtual server from a hosting provider. Multiple isolated spaces are located on one device. Different software can be installed on them. This increases resource utilization efficiency. Memory, computing power, and bandwidth are distributed among virtual servers rather than sitting idle waiting for load. Virtualization is not limited to servers. Storage hypervisors use it for data storage. They run on physical hardware as VMs, within the system, or in another storage network. Hypervisors also help virtualize desktops and individual applications. History of the Hypervisor Virtualization began being used in the 1960s. For the most part, the virtualization environment was applied to IBM mainframes. Developers used it to test ideas and to study and refine hardware concepts. This made it possible to deploy systems and fix errors without threats to the stability of the primary equipment. At the beginning of the new millennium, virtualization received a powerful boost thanks to widespread adoption in Unix family operating systems. There were several reasons for mass distribution: Server hardware capabilities improved. Architecture refinement led to increased reliability and security. Developers began implementing hardware virtualization on processors based on x86 architecture. This led to mass adoption. Since then, virtualization systems have been used not only for solving complex engineering tasks, but also for simple resource sharing and even home entertainment. In recent years, virtualization has expanded beyond x86 to ARM-based processors, with solutions like Apple's Virtualization framework and AWS Graviton instances becoming increasingly common. Advantages of Hypervisors Although virtual machines run on a single device, logical boundaries are built between them. This isolation protects against threats. If one virtual machine fails, others continue to operate. Another huge advantage is mobility. VMs are independent of hardware. Want to migrate an environment to another server? No problem. Need to deploy a VM on a local computer? Also a simple task. Less connection to hardware means fewer dependencies. Finally, resource savings. A hosting provider manages equipment more rationally by providing one physical server to multiple clients. Machines don't sit idle, but bring benefit with all their capabilities. Clients don't overpay for physical equipment while simultaneously gaining the ability to scale quickly and conveniently if such a need arises. Types of Hypervisors There are two types of hypervisors, concisely named Type 1 and Type 2. TYPE 1: bare-metal hypervisors. They run on the computer's hardware. From there, they manage the equipment and guest systems. This type of virtualization is offered by Xen, Microsoft Hyper-V, Oracle VM Server, and VMware ESXi. Modern cloud providers also use specialized Type 1 hypervisors like AWS Nitro and KVM-based solutions. TYPE 2: hosted hypervisors. They operate within the system as regular programs. Virtual systems in this case appear in the main system as processes. Examples include VirtualBox, VMware Workstation, VMware Player, and Parallels Desktop. To increase the stability, security, and performance of hypervisors, developers combine features of both types, creating hybrid solutions. They work both on "bare metal" and using the host's main system. Examples include recent versions of Xen and Hyper-V. The boundaries between bare-metal and hosted hypervisors are gradually blurring. However, it's still possible to determine the type. Though there's usually no practical need for this. Hypervisor Comparison Virtualization types are not the only difference. Hypervisors solve different tasks, have different hardware requirements, and have licensing peculiarities. Hyper-V A free hypervisor for servers running Windows OS. Its features: No graphical interface; configuration and debugging must be done in the console. Licenses must be purchased for all VMs running Windows. No technical support, although updates are released regularly. Hyper-V uses encryption to protect virtual machines and also allows reducing and expanding disk space. Among the disadvantages: there's no USB Redirection needed for connecting USB devices to virtual hosts. Instead, Discrete Device Assignment is used, which is not a complete replacement. VMware VMware is a virtualization technology created by the American company of the same name. It's used to organize virtual server operations. In 2024, Broadcom acquired VMware and introduced significant changes to licensing models and product portfolios, shifting focus toward larger enterprise customers. Many know about ESXi, a hardware hypervisor built on a lightweight Linux kernel called VMkernel. It contains all the necessary virtualization tools. A license must be purchased for each physical processor to operate. The amount of RAM and how many virtual machines you plan to run on your equipment doesn't matter. Note that under Broadcom's ownership, licensing models have evolved, with many standalone products being bundled into subscription packages. VMware has free virtualization tools. However, their capabilities are insufficient for professional use. For example, the API works in read-only mode, and the number of vCPUs must not exceed eight. Additionally, there are no backup management tools.  VMware Workstation The VMware Workstation hypervisor was created in 1999. Now it's a virtualization tool for x86-64 computers with Windows and Linux. The hypervisor supports over two hundred guest operating systems. VMware Hypervisor has a free version with reduced functionality, typically used for familiarization and testing. In 2024, Broadcom made VMware Workstation Pro free for personal use, making it more accessible to individual users and developers. KVM An open-source tool designed for Linux/x86-based servers. Intel-VT and AMD-V extensions are also supported, and ARM virtualization extensions are increasingly common. The KVM hypervisor is quite popular. It's used in many network projects: financial services, transportation systems, and even in the government sector. KVM is integrated into the Linux kernel, so it runs quickly. Major cloud providers use KVM as the foundation for their virtualization infrastructure. However, some disadvantages remain. Built-in services are not comparable in functionality to other hypervisors' solutions. To add capabilities, third-party solutions must be used, such as SolusVM or more modern management platforms like Proxmox VE. KVM is being refined by a community of independent developers, so gradually there are fewer shortcomings in its operation. The quality of the hypervisor is confirmed by hosting providers who choose it for virtualization on their equipment. Xen Xen is a cross-platform hypervisor solution that supports hardware virtualization and paravirtualization. It features minimal code volume. Modules are used to expand functionality. Open source code allows any specialist to modify Xen for their needs. Oracle VM VirtualBox Oracle VM VirtualBox is a cross-platform hypervisor for Windows, Linux, macOS, and other systems.  It is one of the most popular hypervisors, especially in the mass market segment. This is partly because VM VirtualBox has open source code. The program is distributed under the GNU GPL license. A distinctive feature: VirtualBox offers broad compatibility across different host and guest operating system combinations, making it ideal for development and testing environments. Hypervisors vs. Containers Hypervisors are often contrasted with containers. They allow deploying a greater number of applications on a single device. You already know what a hypervisor is and how it works. The problem is that VMs consume many resources. To operate, you need to make a copy of the operating system, plus a complete copy of the equipment for this system to function. If you allocate a nominal 4 GB of RAM to a VM, then the main device will have 4 GB less RAM. Unlike VMs, a container only uses the operating system's resources. It also needs power to run a specific application. But much less is required than to run an entire OS. However, containers cannot completely replace VMs. This is partly due to the increased risk of losing all data. Containers are located inside the operating system. If the host is attacked, all containers can be damaged or lost. A virtualization server creates multiple virtual machines. They don't interact with each other; there are clear boundaries between them. If one machine is attacked, the others remain safe. Along with all their contents. In modern infrastructure, containers and VMs are often used together. Container orchestration platforms like Kubernetes typically run on virtual machines, combining the isolation benefits of VMs with the efficiency of containers. This hybrid approach has become the standard for cloud-native applications. Security Issues Hypervisors are more secure than containers. However, they still have problems. Theoretically, it's possible to create a rootkit and malicious application that installs itself disguised as a hypervisor. Such a hack is called hyperjacking. It's difficult to detect. Protection doesn't trigger because the malicious software is already installed and intercepts system actions. The system continues to work, and the user doesn't even suspect there are problems. To protect the system from rootkits, specialists are developing various approaches that protect it without negatively affecting performance. Modern processors include hardware-based security features like Intel TXT and AMD Secure Encrypted Virtualization to help prevent hypervisor-level attacks. How to Choose a Hypervisor The choice is vast: VMware or VirtualBox, Hyper-V or KVM. There's one universal recommendation: focus on the tasks. If you need to test an operating system in a virtual machine on a home computer, VirtualBox will suffice. If you're looking for a solution to organize a corporate-level server network, then the focus shifts toward VMware tools (keeping in mind recent licensing changes), KVM-based solutions like Proxmox, or cloud-native options. For cloud deployments, consider managed hypervisor solutions from providers like Hostman, AWS, Azure, or Google Cloud, which abstract away much of the complexity while providing enterprise-grade performance and security.

What is a cloud? It’s virtualized server resources: RAM, processor power, disk space, and installed applications. The main advantage of the cloud-based approach to infrastructure is flexibility. If you need more performance, you can easily add memory or connect additional processing power when the load increases. Difference Between Private, Public, and Hybrid Clouds Below is the standard classification of cloud services: Private Cloud: The infrastructure is used by only one organization. The equipment can be located either at the provider’s site or on the user’s premises. Public Cloud: The infrastructure is shared by all registered users. Examples include Amazon Web Services, Microsoft Azure, and Hostman. Hybrid Cloud: A combination of private and public infrastructure. Part of the equipment may be located with the user, and part with the provider. From this classification, it’s clear that hybrid clouds are a compromise solution. However, using them isn’t always justified. To understand this better, let’s compare all three types across several parameters. Comparison Table Parameter Private Public Hybrid Complexity High level of complexity. Requires selecting equipment and developing architecture. Low level of complexity. You choose a suitable service and pay for it. High level of complexity. You need to configure the private part and connect it with the external infrastructure. Cost Expenses are borne by the owner of the equipment and licenses. Expenses are borne by the provider; the user pays a service fee. Expenses are partly on the user, partly on the provider. Maintenance The organization must monitor the system and fix failures itself. The provider manages the infrastructure. The organization must monitor its private part. Scalability Additional resources must be purchased and configured manually. Additional resources are available on demand. Additional resources are available on demand. Security High, as everything is under the owner’s control. Lower level of control; many security aspects remain the provider’s responsibility. High level of security with proper architecture, when all critical nodes are located in the private cloud. Private Cloud Advantages and Disadvantages The comparison table above clearly shows the pros and cons of private clouds. Let’s look at them in more detail. Advantages: Physical access to the equipment usually remains only with the owner. It’s also possible to limit internet connections to prevent unauthorized data access. You can save on physical equipment by investing in the development of a virtual infrastructure instead. Flexible configuration of resources and computing power for different departments within the company. Disadvantages: Requires significant financial investment: you can’t build it without purchasing or renting equipment. System design and deployment take a lot of time. Scalability is limited by the available physical resources. If more capacity is needed, new equipment must be purchased. When to Create a Private Cloud Now that we understand what a private cloud is and what its pros and cons are, let’s figure out when companies choose this approach. The main scenario comes from how a private cloud operates. Large organizations often have enough resources to purchase equipment, design a well-thought-out architecture, and fund teams of specialists to maintain the system. Such companies also tend to handle large volumes of data that require a high level of security. Based on this scenario, the main users of private clouds are: Mobile network operators Banks Insurance companies Gas and oil enterprises Retail companies The types of data that companies host in their private cloud environments can vary, but they generally fall into two main categories: Confidential or proprietary information, for which the organization must retain full control. Security policies or internal regulations may prohibit the use of public cloud servers, leaving private infrastructure as the only viable option. Data governed by strict legal or industry-specific compliance requirements. For instance, certain privacy laws or standards (such as GDPR, HIPAA, or PCI DSS) require data to be stored in secure, controlled environments or within specific jurisdictions. In such cases, a private cloud is often the most suitable solution. It provides greater control over security and compliance, reduces regulatory risks, and allows for certification under relevant industry standards. Moreover, if the company later needs to expand its infrastructure to store or process less sensitive data, it can integrate a public cloud and adopt a hybrid model, combining flexibility with strong data protection.

Hardware virtualization allows creating virtual machines (VMs) on physical hardware while distributing resources as efficiently as possible. This article explains how it works, what types exist, and what advantages it provides for business. How It Works The basic level of any virtualization is the server. Data processing occurs on physical hardware, regardless of the level of abstraction. In hardware virtualization, a hypervisor is installed on the server. This is software that creates sets of virtual resources. There are two main types of hypervisors: Type 1 (bare-metal), which runs directly on the hardware, and Type 2 (hosted), which runs on top of a host operating system. Both create and manage virtual machines, but Type 1 generally offers higher performance. We have covered hypervisors in detail in a separate article. The top layer of abstraction is the virtual machine. At first glance, it does not differ from a traditional server. Essentially, a VM consists of a single virtual disk and files describing its configuration. The virtual machine is installed on the hardware hypervisor. Once the VM is prepared, operating systems and application software can be installed on it. A helpful analogy is a book. Imagine a physical server with installed software as a book on a shelf. You can pick it up and move it physically, but creating a copy to give to someone else requires significant effort: retyping or scanning each page, assembling the pages, and binding the book. A configured VM with allocated resources and installed applications is like a digital version of the book. You can make unlimited copies with minimal time and effort. You can create a backup, transfer a copy to another machine, or share it with another user. Virtualization of CPUs and other resources enables this simplicity in deployment and management. Hardware Support For VMs to function efficiently, resource allocation must be supported at the processor level. Two major technologies exist from leading manufacturers: Intel VT and AMD-V. Both technologies have multiple development directions. The primary one is CPU virtualization, which allows running multiple systems on a single processor, either in parallel or nested within each other. Technologies for virtualized graphics and input/output are also advancing. They facilitate remote access and sharing of physical hardware, which is useful for remote workstations or online gaming. These hardware extensions are particularly important for Type 1 hypervisors, allowing virtual machines to run at near-native performance without modifying the guest operating system. Types of Hardware Virtualization The main types of virtualization are: Full virtualization: hardware is fully emulated. This creates an environment that can run on different servers without lengthy configuration. Paravirtualization: a special version of the operating system is created for the virtual machine. It can be modified or recompiled based on the server's hardware resources. This method was historically used to improve performance, but modern hardware virtualization extensions have largely reduced its advantage. Hardware-assisted virtualization: a fully virtualized VM is created using the computer's physical hardware with support from processor extensions (Intel VT/AMD-V). The choice of type depends on the tasks to be solved. Differences Between Hardware and Software Virtualization Hardware virtualization is not the only approach. Software virtualization relies on a host system and adds an extra layer of abstraction: Physical server with resources Host operating system Hypervisor installed on the host OS (Type 2 hypervisor) Virtual machines installed and managed via the hypervisor Adding this extra layer complicates the process and reduces hardware performance. Physical resources are consumed by both the host OS and the hypervisor. Other issues include: If the host system fails, all VMs running on it lose access to physical resources. Security risks become larger; if the host OS is compromised, all VMs are at risk. Updating or reinstalling the host OS requires stopping the VMs. Software virtualization is suitable for simple tasks, such as testing another operating system inside the main one, avoiding the need to install multiple OSes side by side. For business purposes, hardware virtualization is preferred because it provides higher performance and security. The key is efficient resource usage. Business Advantages Virtualization technology offers several benefits: Cost efficiency: reduces expenses for purchasing, configuring, and maintaining physical hardware. Instead of multiple servers, a single powerful machine can be used, with the virtualization system dividing resources among VMs performing different tasks. Flexibility: VM configurations can be saved as images and deployed across different hardware or moved between servers. Scalability: when workload increases, additional VMs can be quickly launched to add resources and stabilize operations. Fault tolerance: VM snapshots can be created at any time. Copies can be distributed geographically, so even if part of the hardware fails, the infrastructure continues to function. The load on active components can be managed by adding extra resources. Security: VMs are isolated from each other. Compromising one VM does not affect others. Conclusion With hardware virtualization, external applications cannot distinguish virtual machines from physical servers. Guest operating systems run on the CPU without knowledge of other OSes sharing the same hardware. This isolation helps maintain high security. Virtualization is used by large companies, small and medium businesses, and individual users. It enables building a flexible infrastructure of any size that can be easily scaled and protected against internal and external threats.