What is private cloud?

• Public cloud: Resources and cloud storage are owned and managed by a third-party provider (e.g., AWS, Azure, GCP) and shared among numerous customers. This offers cost-effectiveness and scalability but less control and customisation.
   
• Private cloud: Resources are dedicated to a single organisation and can be on-premises or hosted by a third party. This offers greater control, security, and customisation but typically requires a higher upfront investment.
   
• Hybrid cloud: A combination of public and private clouds, allowing data and applications to be moved between them. This approach offers flexibility, scalability, and cost optimisation by leveraging the strengths of both models.

Similarly platform-as-a-service (PaaS) can also be provided on public, private or hybrid basis, while you could rely on infrastructure-as-a-service (IaaS) for your private cloud. For some organizations, the ideal may well be a multicloud solution.

A typical private cloud architecture comprises several key components: compute servers providing processing power, often virtualised for efficient resource utilisation. It doesn’t need to be on-premises infrastructure, it could be hosted by a cloud provider too.

Storage systems for data persistence, including block, file, and object storage, and networking infrastructure connecting the various components.

It also includes server virtualization software creating virtual machines; management software for provisioning, monitoring, and automation.

The architecture can vary depending on the organisation's needs and the deployment model (on-premises, hosted, etc.). Private clouds increasingly incorporate software-defined infrastructure (SDI) to automate further and streamline management.

• Dedicated resources: The hardware and software resources within a private cloud, including servers, storage arrays, and network equipment, are dedicated solely to the organisation. This eliminates resource contention and allows for predictable performance.
   
• Customization and control: Companies have a high degree of control over their private cloud environment. They can customise the hardware, software, and configurations to meet specific business requirements, unlike public clouds, which often offer more standardised offerings.
   
• Enhanced security and compliance: Private clouds offer the potential for enhanced security and compliance due to the dedicated nature of the environment. Organisations can implement stringent security measures, access controls, and data protection policies tailored to their needs and regulatory obligations.
   
• Scalability and elasticity: Private clouds can offer scalability and elasticity while not permanently as elastic as public cloud. You can scale resources up or down as needed, though this often requires more planning and investment than public clouds' almost instantaneous scalability.

Some private clouds incorporate self-service portals, allowing users to provision resources and manage their applications without direct IT intervention. This improves agility and efficiency, mirroring some of the benefits of public clouds. However, the level of self-service can vary depending on the organisation's implementation.

• On-premises private cloud: In this model, the private cloud server infrastructure is located within the organisation's data centre. The organisation retains complete control over the hardware, software, and environment.
   
• Hosted private cloud: A hosted private cloud is managed by a third-party provider, but the cloud private server infrastructure is dedicated to a single organisation. The provider handles the physical infrastructure, maintenance, and often some management aspects, while the organisation retains control over the software, data, and configurations.

Cloud-enabled private cloud incorporates cloud management platforms and tools such as containers to automate and streamline its management. This approach often borrows technologies and best practices from public cloud providers to enable self-service, automated provisioning, and other cloud-like capabilities within the private environment.

• Increased security and data privacy: The dedicated nature of a private cloud environment allows organisations to implement robust DevOps security measures and maintain greater control over their data. This can significantly reduce the risk of unauthorised access and data breaches, offering enhanced data privacy.
   
• Greater control: Organizations have direct control over their private cloud's software and configurations – and hardware, too, if located on-premise. This allows them to tailor the environment to their specific needs and optimise it for their workloads, which is more difficult in shared public cloud environments.
   
• Improved performance and latency: Organizations with dedicated resources and control over the network infrastructure can often achieve better performance and lower latency compared to public clouds. This is particularly important for applications that require fast response times and high throughput.
   
• Compliance with regulatory requirements: Private clouds can be instrumental in meeting stringent regulatory requirements, particularly in industries like finance, healthcare, and government. The control and isolation offered by private clouds make implementing and maintaining the necessary compliance standards easier.
   
• Customization to business needs: Private clouds offer a high degree of customisation. Organisations can tailor the environment to their application requirements, legacy systems, or unique workflows. This level of customisation is often not possible in public cloud environments.

While the initial investment in a private cloud can be higher, it can lead to cost savings in the long run for specific use cases while also supporting cloud security. A private cloud can be more cost-effective than a public cloud for organisations with predictable workloads and a need for long-term resource commitment.

That said, cost savings are highly dependent on the specific circumstances and require careful cost analysis.

• Ongoing maintenance: Unlike public clouds, where the provider handles much of the maintenance, organisations using private clouds are responsible for the ongoing maintenance, patching, updates, and infrastructure management. This requires dedicated IT resources and expertise.
   
• Requirement for specialised IT expertise: Managing a private cloud requires specialised IT skills in virtualisation, networking, storage, and security. Organisations may need to hire or train personnel to effectively manage the private cloud environment.
   
• Limited scalability: Private clouds offer scalability but are often not as seamless or elastic as public clouds. Scaling resources in a private cloud can require physical hardware upgrades or changes to the infrastructure, which can be time-consuming and expensive.
   
• Potential for vendor lock-in: If an organisation chooses a hosted private cloud solution, it may become locked in with the chosen vendor. Switching providers can be complex and costly, making it important to evaluate vendor offerings and contracts.

It’s also worth noting that integrating a private cloud with existing on-premises systems and applications can be complex and challenging. This requires careful planning and execution to ensure seamless interoperability and data flow.

• Organizations with sensitive data: Organizations handling highly sensitive data, such as government agencies or research institutions, often choose private clouds to control their data and minimise the risk of unauthorised access.
   
• Applications requiring high performance: Applications that demand high performance and low latency, such as high-frequency trading platforms or real-time analytics systems, can benefit from a private cloud's dedicated resources and optimised network infrastructure.
   
• Custom software deployments: Organizations with custom software applications that require specific configurations or integrations may find private clouds more suitable. Private clouds allow greater flexibility in customising the environment to meet these applications' unique needs.
   
• Legacy systems modernisation: Private clouds can modernise legacy systems by migrating them to a virtualised environment. This allows organisations to improve the efficiency and scalability of their legacy applications without having to rewrite them completely.

Workloads with specialised requirements are also good candidates for private cloud deployment. Consider high-performance computing (HPC) or machine learning, which often benefits from the dedicated hardware and optimised configurations that a private cloud can provide.

These workloads often require specific hardware accelerators or specialised software that may not be readily available in public cloud environments.

The private cloud landscape is evolving, and one significant trend is the increasing integration of private and public clouds into hybrid cloud environments. Organisations are recognising the benefits of combining the control and security of private clouds with the scalability and cost-effectiveness of public clouds.

A hybrid approach allows them to optimise workloads by placing them in the most appropriate environment.

Automation and orchestration are also crucial in modern private cloud deployments because they streamline operations, reduce manual effort, and improve overall efficiency.

Software-defined infrastructure (SDI) is another technology that is transforming private clouds. SDI abstracts the underlying hardware and allows for programmatic resource control, enabling greater flexibility, agility, and automation in managing the private cloud environment.

It is closely tied to adopting modern application development approaches like containerisation and microservices.

Another exciting trend is the extension of private clouds to the edge. Edge computing brings computation closer to the data source, reducing latency and improving performance for applications that require real-time processing.

Private clouds are being extended to edge locations to support these emerging use cases. Finally, the potential for serverless computing within private clouds is being explored.

Serverless architectures, which abstract away the underlying infrastructure and allow developers to focus solely on code, are gaining traction. While still relatively nascent in private cloud environments, serverless computing has the potential to enhance agility and efficiency further.