Address Cloud Computing Security Concerns with Private Cloud

Cloud computing in the public cloud has raised security questions for businesses that have regulatory compliance requirements. Many regulatory agencies have been slow to align security requirements with public cloud computing. This creates barriers to adopting public cloud for security-sensitive applications. To meet some of these security needs, businesses use a private cloud to achieve the benefits of cloud computing while maintaining
the security and privacy that dedicated hardware provides. Private cloud computing also offers users a path for future migration to the public cloud. This article describes security concerns in the public cloud and strategies for employing private cloud to address these issues.

Protection against hackers

The first security concern in any computing environment is the threat from hackers. Cloud computing in a shared environment creates new opportunities for hackers seeking to discover vulnerabilities that might allow them to deny service or gain unauthorized access. Additionally, security experts have detailed methods for attacking cloud infrastructure from the inside by running hacker tools in the cloud.

When a hacker has access to a public cloud node, the hacker gains greater visibility inside the cloud. The hacker then uses this inside information to probe the system and plan attacks more effectively. To combat this vulnerability, a private cloud restricts access to its resources to authorized users and administrators only. By preventing potential hackers from gaining an inside view, private cloud allows businesses to tightly control access to the entire environment.

Protection against resource contention

Another concern of public cloud is resource contention. A security issue can arise when resource contention results from a Denial of Service (DoS) attack on another tenant of the shared infrastructure. The public cloud is a shared resource that can potentially expose all tenants in the cloud to security risks when any tenant becomes the target of a DoS attack. However, private cloud provides businesses with inherent protection from DoS attacks directed at other businesses by avoiding shared infrastructure.

Many regulatory compliance specifications, including the Health Insurance Portability and Accountability Act of 1996 (HIPAA) and Payment Card Industry Data Security Standard (PCI DSS), specifically require data segregation (although not all public clouds use virtualization technology). These standards have not been updated to address data protection and segregation in the public cloud. Rather, they align with the private cloud. Because a private cloud uses dedicated hardware, it is comparatively simple to segregate the data on separate servers and virtual machines (VM).
This allows businesses to maintain regulatory compliance while benefiting from cloud computing.

The preceding example includes the following components:

  • Hypervisors: Physical servers that run the various virtual machines under hypervisor control.
  • Firewall: The first line of defense against attacks.
  • IDS: Intrusion Detection System.
  • DMZ segment: The demilitarized zone (DMZ) network segment has tightly controlled access to the public Internet.
  • Private segment: This network segment has no access from the public Internet.

This custom configuration includes both a public and a private segment, a firewall, and IDS hardware. In this example, the two network segments enable the publication of applications in a compliant manner regardless of whether you need a public or private network. Private network segments prohibit access from the public Internet and are a necessary component of many regulatory compliance specifications such as PCI DSS. The IDS device proactively detects any incoming attacks and send alerts prompting the security staff to investigate and respond.


Cloud computing is constantly evolving and is likely to address these security concerns as technology advances. Technology will soon allow virtual machines to move from private clouds to public clouds and back again. Businesses that choose to deploy a private cloud today can benefit immediately by making the best use of their available resources. In addition, the businesses using private cloud to optimize their environments are better positioned for a future transition to public cloud as their needs evolve and new technologies emerge.