Cloud services are broadly grouped by whether they are public or private. In a public cloud, multiple organizations share the cloud servers and infrastructure. Examples are Amazon, Google, and Microsoft. In a private cloud, one organization owns all the servers and infrastructure. The main reason people would choose private cloud is having complete control of performance, reliability, and security. Cloud services are also grouped by how they function: Infrastructure as a Service (IAS), Platform as a Service (PAS), and Software as a Service (SAS). IAS includes servers, storage, firewalls, security, data center and physical facility. This is typically used for disaster recovery. PAS builds on IAS by adding operating systems and development tools. This is typically used for developing and testing new applications. SAS is the most common cloud service and builds on PAS by adding applications. Examples of SAS are Microsoft 365, Salesforce, Google and G-Suite.

The use of cloud services is steadily increasing, but there are situations where they are not the best solution. Reasons to avoid the cloud are unreliable Internet connection, slow Internet connection, and absolute need to control performance, reliability and security. For most of us who are not in any of the previously mentioned situations, cloud computing provides low startup cost scalability, and availability. Since you can start with a single license and generally don’t need to upgrade your computer to run a cloud application, the startup costs are limited to the software and training. Cloud vendors own massive data centers with thousands of servers so adding two, three or a hundred additional users won’t add any incremental infrastructure costs. Since cloud servers are accessible for any Internet connection, you can access your cloud services from anywhere!

Besides providing the desired service at an agreed to cost, a cloud service agreement should have minimum standards for performance and reliability. It should be stated in measurable metrics with penalties for non-compliance. The other important area is security. Cloud security is a shared model. The end user is responsible for the security of their computer and the cloud provider is responsible for security the data while it is transit between your computer and their data center and while it is stored at their data center while not in use. You should have the ability to shift legal responsibility for breaches to the cloud provider when they are at fault. Lastly, you need to have an orderly way to terminate the agreement in case things don’t work out. The most important aspects of termination are how quickly it happened and how to retain your data in a useful format.