Private Cloud In Cloud Computing: Benefits and When To Use

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.

Virtual Data Center is infrastructure resources in the “cloud” allocated for business needs. Physically, the equipment is located in traditional data centers. The provider rents it out using virtualized space. A virtual data center (vDC) can be managed from anywhere in the world via a console. At the same time, the flexibility of such a solution is higher than that of a traditional data center. There are also advantages in terms of cost efficiency, scalability, and security, which we will discuss below. Virtualization Layers A virtual data center is a multi-layered system, where virtualization is applied at each level. There are five main layers: Network. Virtualization allows configuring communication between multiple servers to build a unified infrastructure. Storage. Administrators manage file placement at this level, which is convenient even if the data is stored on different devices. Resources. Virtualization enables flexible adjustment of available computing power, changing resource usage based on business needs. Applications. Virtualization solves compatibility issues, allowing applications to run independently of the host operating system. Access. User rights management, for example, for remote system access. These layers are interdependent. A virtual data center operates correctly only if interactions between the layers are properly configured. vDC Capabilities The main advantage of a virtual data center is the ability to quickly scale resources up or down, allowing businesses to address various tasks without contacting the service provider. Other important capabilities include: Data protection. Storing information in a vDC significantly reduces the risk of data loss, especially when backups are properly configured and geographically distributed. Disaster recovery. With a simple and fast backup system, the infrastructure can be restored within minutes. Flexibility. IT teams can automate routine tasks, quickly implement and test new systems and features. Reliability. Providers use high-performance equipment and maintain the physical infrastructure of the vDC. Control. All monitoring and management tools are available to the customer who ordered and paid for the resources. Cost savings on hardware. There is no need to buy, configure, or maintain physical equipment; the provider handles this. Customers pay only for the resources they use. Another important aspect is the availability of different billing models. Customers can either pay a fixed monthly amount for allocated resources or only for the resources actually consumed. Both models guarantee that the provider will allocate the requested resources, preventing situations where the client requests capacity but does not receive it in full. Scalability Features One of the main advantages of a virtual data center is rapid scalability. When demand increases, add resources; when demand decreases, reduce unused capacity to save costs. Scalability can be of two types: Horizontal scaling: new elements are added. For example, if an application normally runs on two servers but user demand increases fivefold, additional servers can be added and users distributed among them. Vertical scaling: additional resources are added to an existing server. For instance, RAM can be increased, storage expanded, or the server replaced with a more powerful one if the CPU cannot handle the load. Horizontal and vertical scaling are not mutually exclusive and often complement each other. Horizontal scaling is usually used for expanding server clusters, while vertical scaling is applied when increasing load without adding new servers. A single task can be addressed with either horizontal or vertical scaling in a vDC. Example: A web server hosting a website experiences increased traffic. Vertical scaling would involve adding CPU, RAM, or storage to the existing server. Horizontal scaling would involve cloning the server and distributing the load across multiple virtual machines. Use Cases A virtual data center can fully replace physical infrastructure and help address almost any business task. Common scenarios include: Data storage Software development and testing Increasing capacity using reserve resources during peak loads Creating a backup data center that fully replicates the main data center Setting up remote workstations These are just a few typical use cases. In practice, vDCs can be beneficial in many situations. However, this solution is not suitable for everyone, partly because vDCs are usually more expensive than standalone cloud servers. Suitable for: Medium or large companies planning or already migrating some processes to the cloud. Companies with seasonal fluctuations or plans to increase load. Startups that need to minimize infrastructure costs initially but be prepared for rapid growth. The final decision on whether to deploy a virtual data center should involve IT specialists, economists, analysts, and managers responsible for strategic development, so everyone understands what a vDC is and the risks and benefits of its implementation.

VMware NSX is a platform for the virtualization and security organization of network services. NSX helps configure routing, distribute loads, manage firewalls, and perform other tasks that system administrators constantly face. What Problems NSX Solves Here’s a common situation: the firewall configuration becomes a long list of addresses, ports, subnets, and protocols. At first, the system administrator keeps order and follows logical structure—perhaps even leaves comments for colleagues and successors. But over time, disorder grows. Employees change, the administrator leaves, and the configuration becomes impossible to modify without risking the entire system. Each day, the tangle gets more and more complicated. To reduce such situations, VMware once introduced CNS vShield Edge. It was a separate virtual machine that worked as a boundary gateway. The administrator could configure most network functions there. Firewall and NAT rules were used to limit interaction with external networks. If one really wanted to separate traffic, it was possible to create a separate network for different VMs and write network interaction rules in the firewall. But that was not a pleasant task—especially if the infrastructure consisted of several dozen VMs. VMware NSX replaced CNS vShield Edge. Its main feature is a distributed firewall built into the hypervisor. In it, you can define interaction policies for any object: IP, MAC, virtual machine, application, or device connected via VMware PCI. Each object gets its own security perimeter, which can be flexibly configured. Key Capabilities We already briefly mentioned one capability—network microsegmentation. It is implemented through the distributed firewall. This feature allows for precise control of security policies for VMs and applications. Thanks to microsegmentation, you don’t bombard the entire system with broad restrictions. It also reduces the risk of lateral (horizontal) threat propagation within the data center. One compromised segment is not a death sentence. Another useful feature is the easy movement of network objects. For example, you can take a VM with data and move it to another segment or even another virtual data center. The rules for that VM will continue to apply regardless of its new location. The physical network topology also doesn’t matter; the only requirement is that communication with the previous virtual data center remains. By removing network and security tool limitations, the virtual environment is no longer tied to physical hardware. This increases resource utilization efficiency and significantly speeds up network initialization. NSX Architecture The VMware NSX platform consists of several components: Controller Cluster: a system made up of physical or virtual machines (at least three). It is designed for deploying virtual networks. All machines work in high-availability mode and receive commands through an API. The cluster manages vSwitches and Gateways, which implement virtual networks. Essentially, the Controller Cluster defines network topology, analyzes traffic, and determines how to configure network components. NSX Manager: a tool that helps manage virtual networks through a web console. It interacts with the Controller Cluster. Hypervisor vSwitches: virtual switches that handle virtual machine traffic. Gateways: components that connect virtual and physical networks. Ecosystem Partners: components through which partners can integrate their virtual modules. The server hypervisors in an NSX system can be VMware vSphere, KVM, or Xen. Zero Trust Features The NSX network virtualization platform allows implementation of the Zero Trust Security model. It is effective for defending against attacks targeting the least protected parts of the system. The core principles of this concept are: There are no trusted segments or objects: everything is verified. Users are given minimum privileges, and access requires explicit permission. Transparent and secure access to resources is provided regardless of their location. All traffic is monitored and analyzed. VMWare’s application virtualization helps create security segments for individual objects, implementing the principles of zero trust. This ensures the entire system has a high level of protection against unauthorized access. Use Cases VMWare NSX virtualization is applied to solve various tasks. Let’s look at a few common scenarios. Data Center Security The most logical use case is dividing a data center into many security segments, each with its own rules. The configuration does not depend on the environment in which the segment operates and is based on user and application behavior scenarios. Microsegmentation helps network administrators instantly detect threats and begin neutralizing them. This approach also greatly reduces the risk of lateral threat spread—the key distinction between NSX and traditional networks. Even if an attacker breaches the perimeter defense, they cannot move laterally within the data center. To ensure security and control over interactions, NSX provides a wide range of tools: Dynamic routing Load balancer for even traffic distribution Distributed firewall Command-line interface, monitoring, and troubleshooting tools for convenient operation Additionally, VMware Mail can be configured to receive instant notifications about operational issues. Automation of Network and Application Deployment Before NSX, network initialization was done manually; it required a lot of time and resources and often led to errors. NSX eliminates these issues completely. Networks are created programmatically, removing bottlenecks tied to physical infrastructure. By virtualizing network and security services, application lifecycle management can also be automated. Developers can offload routine deployment and maintenance operations, freeing time for other tasks, such as reducing technical debt or implementing new business features. Migration of Services and Applications The VMware NSX concept separates the network from physical hardware. Security policies are bound to specific workloads, allowing services and applications to be migrated between data centers in minutes. Data can be replicated to remote sites, and applications can be deployed without interacting with the physical layer—all without any downtime, not even for a moment.