The Advantages and Disadvantages of Private and Public Cloud Computing Solutions
Cloud computing continues its strong adoption, but the debate over which cloud deployment platform continues. Cloud computing solutions can deliver serious benefits, although each deployment option has its own advantages and drawbacks. In certain situations, the benefits can outweigh the risks, so you need identify situations in which the cloud will help you reap the maximum rewards with minimum risk.
To choose which cloud computing solution option is appropriate for your company, you’ll need to consider and balance a number of factors. We’ve weighed a few of the advantages and disadvantages between a public cloud—Amazon EC2, in this case—and a private cloud at a co-located data center. This isn’t a comprehensive comparison by any stretch, but hopefully this can help move you in the right direction.
Here, we’ve compared scalability, per-hour computing costs, and reliability and risk management. The ‘per-hour computing costs’ in this comparison are based on a three year purchase or lease. For a more detailed financial comparison of private versus public computing solutions, please visit our blog on the subject.
Public Cloud Computing Solution (Amazon EC2)
The scalability of a public cloud computing solution is typically very simple and immediate. The storage is also scalable to accommodate growth, and it’s easy to switch between performance categories. The downside is that there’s a higher cost per-hour that becomes aggregated with additional computing resources. Scaling up for increased performance can also multiply your cost by a factor of two or more, and there’s a fixed level of CPU and RAM per category.
The ‘per-hour computing costs’ for a public cloud is fairly easy and transparent; it’s OpEx versus CapEx and employee costs. On the downside, the costs are variable and subject to change at the whim of the provider. In addition, there’s no scalability within an instance—rather it’s per instance so you’ll need to watch costs carefully. Storage costs are calculated on top of computing costs, so you’ll also need to monitor this carefully.
In terms of reliability and risk management, there’s little control over where systems are located or whether redundancy exists. They’re also notoriously unreliable with little guarantee of uptime.
Private Cloud Computing Solution
If your private cloud solution is virtualized, you can scale it nearly as quickly as a public cloud offering with limited additional costs. You’d have CapEx costs, but they could be converted to OpEx costs through leasing options. The performance scaling is incremental—you can scale out, scale up, or scale within all quite easily. You can also maintain and support machines with different performance levels or a development and testing environment.
The only real downside to a private cloud computing option is that you’ll need to amortize costs if you purchase the equipment.
When calculated over a three year term, the ‘per-hour computing costs’ for both hardware and software are generally lower. You have the option to purchase or lease, and if you lease, the equipment is yours at the end of the lease term.
A private cloud clearly differentiates itself from its public cloud counterpart in the reliability and risk category. With a private cloud, you can easily increase the level of support you need to cover power redundancy. Four integrated Gigabit Ethernet ports enhance network availability and can be installed in failover configurations. In addition, on-board system management tools encourage proactive remote monitoring and intervention.
Depending on your computing environment and needs, what levels of security and scalability you require, each cloud computing deployment option can play a role. Don’t forget—a hybrid cloud may best suit your needs.