Before the 1990s, operating systems were installed on physical machines in customer-owned data centers. This changed with the rise of virtualization and containerization. Both technologies allow more code to run on less hardware and have developed and grown alongside cloud computing. As a result, they allow businesses to save energy, space, and maintenance costs. Increased security can be among the benefits of implementing containerization and virtualization, but only if businesses and professionals are aware of and vigilant toward the unique security considerations presented by each technology.
Pros and cons of virtualization
Virtualization is a process that allows a physical machine with computing, network, and storage to share its resources with multiple virtual machines, thereby enabling the consolidation of physical servers. Virtual machines run multiple operating systems on an underlying hypervisor. They are flexible and easy to manage. Because virtualization permits multiple operating systems to run independently, it isolates workloads, facilitating easy disaster recovery solutions. It also saves money and resources by reducing the amount of physical hardware needed. Databases and significant applications are well-suited to running on virtual machines.
Virtualization, however, is not without its drawbacks. The amount of memory, central processing unit (CPU), and disk space involved in running several virtual machines is considerable. Also, each virtual machine requires its own operating system license. Therefore, virtualization is not ideal for all situations. Identifying good use cases is an essential part of the successful deployment of virtual machines.
Pros and cons of containerization
Containerization enables the deployment of code inside a portable, secure, lightweight application that contains all required files, configurations, and dependencies. Instead of an operating system, containers only have the libraries and tools required to run their applications. Over the past decade, developers have embraced containerization software products like Docker because they make building and deploying cloud-native applications simpler.
Containers offer low cost and resource usage. They are portable, flexible, and allow quick deployment of applications. In addition, their built-in version control permits easy access to previous versions. The disadvantage is that the infrastructure required to host containers is complex. It requires a hybrid infrastructure and development team to implement and support.
Security implications of virtualization
Regular patching of the hardware and hypervisor is critical for maintaining a safe and secure virtual environment when running on-premise. When running on the cloud, the cloud provider will manage the patching of the hardware and the hypervisor. In both scenarios, regular patching of the operating system is critical.
If a virtual machine is compromised, it should be shut down and isolated to avoid further damage. However, if attackers compromise the underlying hypervisor, they can take control of all the associated virtual machines.
During the deployment of a virtual machine, it is crucial to ensure that the right policies and configurations are used and that public access is not enabled by default. This is still true if the virtual machine runs in the cloud. Additionally, virtual machine image management requires careful attention, including regular image audits. The security risks associated with virtualization can be reduced by implementing strong access controls, network segregation, and encryption. Typically, virtual machines have multiple applications installed and therefore, it is important to schedule periodic vulnerability and penetration testing.
Security implications of containerization
Containers have a smaller attack surface when compared to virtual machines. There are, however, security concerns to consider. The greatest is container eruption, in which an attacker gains access to the underlying host operating system by exploiting a vulnerability in the container. The container image, engine, and orchestration systems must be updated with the latest security patches and scanned regularly for potential vulnerabilities. Organizations should conduct routine audits and implement container-specific security policies and processes. Regular releases and updates as part of the continuous integration and continuous delivery (CI/CD) pipelines can help or address vulnerabilities.
In the past, security was primarily the responsibility of an operations (Ops) team, but with the advent of containerization, security starts with developers. As container usage increases, orchestration systems like Kubernetes play a critical role in minimizing risk by offering pod security policies to help secure container development. Container monitoring and scanning tools can analyze logins, code, and configurations to address vulnerabilities before deployment. Permission management is also important to ensure proper container security. Container runtime security is especially critical and difficult to monitor. Cybersecurity teams can tackle this challenge by focusing on application security and deploying container firewalls to monitor ingress and egress traffic. Because of the scarcity of cybersecurity professionals, companies need to consider automating manual security processes to minimize the risk of attacks.
Creating a secure solution with both containerization and virtualization
Virtualization saw widespread adoption in the late 1990s, and now containerization is seeing similar exponential growth that will likely continue. Containerization and virtualization each have their strengths. Containerization is the right choice for deploying cloud-native applications and package microservices and moving scalable apps across IT environments. While it is more secure, it’s not ideal for situations where an application requires full functionality of an operating system. Virtualization is a better choice in these use cases and for those where multiple applications are being deployed on the same server.
Because containerization and virtualization have advantages, drawbacks, and ideal uses, top organizations across various domains including retail, auto, and manufacturing, utilize systems that incorporate both solutions. They have benefited from increased speed and flexibility of deployment and reduced dependence on physical hardware, which leads to cost and resource savings. Proper management, including hardware updates, OS patches, network segregation, scanning, and monitoring, is vital for maintaining the security of containers and virtual machines. Therefore, combining containerization and virtualization while paying careful attention to the security considerations posed by each is vital in helping companies to form a secure and efficient IT infrastructure.
About the Author
Srinivas Kunta is an IT solutions architect with more than 15 years of experience in SAP and infrastructure management. He is a subject matter expert in SAP Basis, integrations, and cloud solutions. Srinivas holds a bachelor’s degree in computer applications from Osmania University, India and can be reached at firstname.lastname@example.org.
Disclaimer: The author is completely responsible for the content of this article. The opinions expressed are their own and do not represent IEEE’s position nor that of the Computer Society nor its Leadership.