Understanding Cloud Computing

The three service models, in plain terms

Software as a service is what you already use: Microsoft 365, an accounting platform, a CRM. You open a browser and it works. You manage users and data; the provider manages everything else.

Infrastructure as a service is renting the equivalent of servers and storage. You get flexibility and control, and in exchange you are responsible for the operating system, patching, and configuration. Azure virtual machines live here.

Platform as a service sits between them: the provider manages the operating system and runtime, and you deploy your application. Most businesses encounter this indirectly, through managed database or web hosting services.

What genuinely improves

Availability. Well-designed cloud services run across multiple data centres, so a single hardware failure is not an outage for you. Achieving that with equipment in one office is expensive and rarely done well.

Recovery. Backups held outside your building survive fire, flood, theft, and ransomware that reaches your network. This is often the strongest argument for cloud in a small business.

Remote and mobile working. Your team reaches the same systems from anywhere without a VPN appliance to maintain, which matters more now than it did five years ago.

And capacity. Adding a new starter no longer means ordering a machine and waiting; it means creating an account.

Where the hidden costs sit

Cloud is usually cheaper for small, variable workloads and more expensive for large, steady ones. A server that runs at full capacity all day, every day, is often cheaper to own over several years than to rent.

Bandwidth is the classic surprise. If your business moves large files, or runs an application in the cloud that your office uses all day, your internet connection becomes infrastructure rather than a utility — and the cheap line will not carry it.

Licensing is the other one. Cloud subscriptions are per user, per month, forever. The old model had a large upfront cost and a long useful life. Budgeting has to change shape, not just size.

And exit costs. Moving data out of a cloud provider can be slow and sometimes chargeable. It is worth knowing the answer before you commit, not when you want to leave.

Choosing what to move first

Start with the things cloud does unambiguously better: email, file sharing and collaboration, and backup. These are mature, well-supported, and the operational gains are immediate.

Be more careful with line-of-business applications whose vendor support, integration, and performance characteristics in the cloud you have not confirmed. Ask the vendor directly what their cloud deployment looks like in practice.

Keep in mind that a hybrid outcome is normal and fine. Plenty of well-run businesses keep some workloads on-premises and move others to the cloud, because that is where each one performs best.