There are two broad approaches to cloud infrastructure. Public cloud shares resources across many tenants on the provider's hardware. Private cloud dedicates the infrastructure to a single organisation. Knowing how they differ is what lets you decide where each workload actually belongs.
Architectural differences
Public cloud platforms like AWS, Azure, and Google Cloud operate on a multi-tenant model. Your virtual machines, storage, and networking share physical hardware with other customers. The provider manages everything from the data centre to the hypervisor layer, and you consume resources on demand through APIs and web consoles. This abstraction is powerful for rapid provisioning, but it means you have limited visibility into the underlying infrastructure.
Private cloud, by contrast, provides dedicated hardware and networking for a single organisation. This can take several forms: on-premises infrastructure managed by your own team, colocated hardware in a third-party data centre, or a managed private cloud operated by a provider like Anchras. The key distinction is isolation. Your compute, storage, and network fabric are not shared, which gives you full control over configuration, security policies, and performance characteristics.
Security and compliance
In a public cloud environment, security is a shared responsibility. The provider secures the infrastructure layer, while you are responsible for securing your applications, data, and access controls. This model works well for many use cases, but it introduces ambiguity. When a security incident occurs, determining whether the root cause lies in the provider's infrastructure or your configuration can be complex and time-consuming.
Private cloud simplifies the security boundary. Because the infrastructure is dedicated, you have complete control over network segmentation, encryption policies, access management, and audit logging. For organisations subject to ISO 27001, SOC 2, or sector-specific regulations like those in healthcare and finance, this level of control is often a requirement rather than a preference. You can implement security policies at the hardware level, enforce physical access restrictions, and maintain a complete chain of custody for your data.
Cost models: predictable vs. pay-as-you-go
Public cloud pricing follows a consumption-based model. You pay for what you use, which sounds efficient in theory. In practice, costs can be unpredictable. Egress fees, cross-region data transfer charges, and the complexity of reserved instance pricing mean that many organisations end up spending significantly more than their initial estimates. A 2025 Flexera survey found that organisations reported an average of 28 percent cloud waste in their public cloud spending.
Private cloud operates on a capital expenditure or fixed monthly fee model, depending on whether you own or lease the hardware. Your costs are predictable month to month, and there are no surprise charges for data transfer or API calls. For workloads with consistent resource requirements, which describes the majority of enterprise applications, private cloud often delivers a lower total cost of ownership over a three to five year period. The Anchras Platform is built for this profile, exchanging consumption-priced volatility for a predictable per-month line item against dedicated capacity.
When private cloud wins
Private cloud is the stronger choice in a few common situations. If you handle sensitive data, like health information, financial records, or legal documents, the isolation matters. If your workloads are predictable, you skip the cost swings of pay-as-you-go. If you are bound by data residency rules, you can keep infrastructure inside a specific jurisdiction. And if public cloud has already locked you in once, the portability is worth a great deal.
That said, public cloud remains well-suited for highly variable workloads, rapid prototyping, and scenarios where global distribution of resources is a primary requirement. Many organisations ultimately adopt a hybrid approach, running core workloads on private infrastructure while using public cloud for burst capacity or specific SaaS integrations. The Anchras Platform supports this model, providing the private cloud foundation while maintaining the flexibility to integrate with external services as needed.