What's the Difference between Public and Private Cloud?

How do you choose between public and private cloud? What are the differences between them? What are the advantages of private cloud? How do I choose between public and private cloud? Let's have a look at the basics to help make the decision.

Public Cloud

Love them or hate them, you have to hand it to those guys at Amazon. There they were with those huge banks of servers which were working away like crazy at Christmas and Thanksgiving (how did we ever manage Christmas without them?), but with under capacity usage for the rest of the year. So they said 'Hey, why don't we rent out the compute capacity and storage space to other folk?'. And now 12 years later Amazon Web Services is by far and away the world's biggest public cloud service provider. For me, it is Amazon Web Services that springs to mind when I think of a public cloud - a huge farm of servers providing storage and processing power on demand, expertly controlled by the cloud provider. And that, essentially, is what public cloud is.

Good stuff about public cloud

So what are the advantages of public cloud?
* Little or no initial capital outlay. You don't have to invest in a farm of servers
* Scalability. You can increase and reduce your usage easily and quickly
* Highly competent people in charge. Companies like Amazon can afford to employ the experts in the field
* Electricity costs are reduced at your end. Let the cloud provider pay for running all those machines.
* Expenditure on maintenance contracts is reduced. You have less hardware and software to maintain

What to watch out for when going public

• You have little to no control over where your data is located.
• Costs can get out of control. The cost per hour can be changed by the provider without consultation with the user. Look closely at the pricing plans and details for each application.
• Possible downtime. Even the big guys can have outages and that means your system is down too.
• Inflexibility. You could be locking yourself into using their applications or formats.

If your data is not hyper sensitive, then this could be the right, cost-effective choice for you.

So what's the difference between public and private cloud?

Private Cloud

• Greater control. You are in charge of monitoring and maintaining the data
• More control over security. This will be an issue if you deal with highly sensitive data or work in a industry with particularly stringent regulations on data security
• Customisation. Hardware, network and storage can all be customised to your company's needs

• Initial set-up costs. If you have to invest in a significant amount of hardware, it can become an expensive option.
• Maintenance. You have to pay all the electricity bills, service contracts, think about risk management (what if it all goes up in flames?)
• Space. You need room to house all that equipment.

It is exactly these issues which often prohibit small companies from choosing the private cloud option, even if that is what would be best for them. However, with solutions like the NuvlaBox businesses can have an affordable entry point to private cloud computing.

Do I have to choose?

Actually no, as there is the Hybrid Cloud, which combines features of both public and private cloud. You can keep the most sensitive data in-house and use a public cloud for other applications, making the most cost effective choice for your business. To manage the complexity of handling several clouds, cloud management solutions can be of great help. Of course I recommend you have a look at Nuvla, but there are one or two others as well ;-)