Cloud computing has transformed how we work and play online. But the cloud isn’t one thing; it spans a range of classifications, types, and architecture models.
Most applications and services run “as-a-Service” are run on public clouds. That is, on cloud computing delivered via the Internet and shared across organisations and worldwide. On the other hand, a private cloud is cloud computing dedicated solely to a single organisation, such as your employer. It’s accessible through a closed network that may or may not be hosted on-site. Companies that use both public and private clouds are using a hybrid model.
This article will compare public and private clouds and explore some of their benefits and differences. That way, you’ll be able to decide which option works best for your situation.
The basics of cloud computing
As a quick reminder, cloud computing is the storing or accessing of applications, systems, and data via the Internet instead of directly on your computer. The cloud lets you access a broader variety of applications and systems such as email, data analytics, and other business applications. In recent years, the use of cloud computing has exploded with companies and people going beyond the original Software as a Service (SaaS) applications into Platform as a Service (PaaS,) Infrastructure as a Service (IaaS,) and even Data Centre as a Service (DCaaS.)
Any of these cloud computing options can be set up as a public or private cloud option and make them available to people through the Internet (public) or only on a specific network (private.) Regardless of type, a cloud service consists of client-side systems and devices (laptops, tablets, etc.) connected to the backend data centre components via a network. The backend components consist of network software, hardware devices, storage systems, and virtualization.
What’s the difference between a public and private cloud?
One key difference between public and private clouds is who has access to the clouds.
A public cloud is typically stored on remote third-party infrastructure offered to multiple customers by a cloud provider. Each user is given authorised access to the public cloud to use the application or service. Each customer instance or usage is securely isolated, so data is not shared across customers. They only share the cloud provider’s infrastructure, bandwidth, and system resources as they use the service.
A private cloud is a cloud application or service not shared with any other organisation or customer. It consists of cloud computing resources used exclusively by one business or organisation. It can be physically located in the organisation’s on-site data centre or hosted by a third-party service provider. Even if hosted remotely by a third party, no other organisation has access to the private cloud.
The other differences between the two types of cloud computing are more subtle, so let’s take a closer look.
The subtle differences between public and private clouds
From available technologies to compliance, costs to scalability, there are many subtle differences between public and private clouds.
Both public and private clouds can run on remote hardware and IT infrastructure. Public clouds run on multi-tenant, shared infrastructure, and private clouds run on single-tenant architectures. A private cloud may also be located on-premise in a company’s data centre, while a public cloud will not.
Another area to consider is the availability of the latest and greatest technologies. Public cloud users will always get access to the latest version of applications and systems because the cloud providers pride themselves on ensuring the roll out the newest features and options.
Private cloud customers will need to rely on their internal IT staff or their managed private cloud provider to stay updated on the latest offerings. Internal teams often have other things to worry about and work on, so a private cloud may stay on older versions of applications for longer. A public cloud may provide a slight improvement on this drawback. However, it depends on your company’s service agreement with them. Some providers may only offer update services as an add-on to a regular service agreement, while others may not offer them at all.
Accessibility and security
Public clouds are accessible by authorised users via the Internet, while private clouds are only accessible by authorised users located within a company’s firewall or on their corporate network.
Security on a private cloud can be controlled and monitored more closely since the company has complete control over access and the infrastructure. Public clouds rely on security at various waypoints on the Internet and are more susceptible to attack.
Public clouds are also more mobile-friendly since they are accessible via the Internet. Private ones are not custom mobile connectivity, and authorisation options must be set up for access outside the corporate network.
Since they’re located in and maintained by cloud providers, public clouds offer minimal technical control and visibility into their services. This makes public clouds ideal for companies that use general cloud apps and services to perform IT and business operations.
Companies in highly regulated industries or that deal with sensitive data and information may consider using a private cloud. They offer more robust control, security, and visibility into their IT infrastructure so they can fine-tune their security options as needed. Plus, some security guidelines and laws worldwide require deep visibility into application options and data storage methods, so a private cloud offers more features to do so.
Bandwidth and connectivity
Public clouds depend on the public Internet for bandwidth and connectivity performance, making it a good option for companies with predictable computing needs. Those who require consistent and highly reliable bandwidth and performance should consider using a private cloud since it only depends on the internal number of resources using it. Companies can also throttle the private cloud for high-availability time periods to ensure high-priority workloads are completed as needed.
Costs (Up-front and ongoing)
The main difference here between public and private clouds is the initial cost. Public clouds offer flexible and cost-effective pay-as-you-go models that make it cheaper to get into the market. They help companies reduce spending on hardware and on-premise infrastructure since the cloud provider handles this portion of the workload. That includes passing along overhead maintenance tasks and costs to the provider since it’s on them to do it all. Private clouds have higher up-front costs as they typically require a large, up-front investment in IT infrastructure, resources, and maintenance.
Where the two can even out is with the total cost of ownership (TCO.) Public cloud customers should generally have a lower TCO if they’ve paid attention to their seat usage and overage costs and renegotiated wisely come subscription renewal time. If the company expands rapidly without considering the public cloud costs, things can get just as expensive as a private cloud.
Public clouds can scale up or down more easily than private clouds because they have the necessary infrastructure and resources to do so efficiently. They’re set up to scale up or down as needed and have the proper monitoring tools and IT staff to handle it at a moment’s notice. A private cloud relies on the infrastructure and staff at hand, so if your company’s run out of bandwidth on the infrastructure you have, you’re stuck until you add more hardware.
The applications and services available in the public cloud span every kind of architecture, platform, and business need. With so many “as-a-Service” offerings out there, many companies will never have to own or buy infrastructure again. But if you’re in a highly regulated industry, are looking for more stringent control over your infrastructure, or have the money reserves to do it, a private cloud may be the option for you.
Your cloud choice will be driven by your requirements, your industry, and your business goals. For more help on determining which option is right for you, reach out today. Our cloud consultancy service can guide you through the process and help you find the right cloud strategy.