What is the difference between public and private cloud computing services?

Randy,

The public cloud solution (commercial) offers small companies access to large company applications managed by professional IT people. They can also offer best practice security that can be expensive if you purchase on your own. From an economic standpoint, the cloud is popular since there is usually not a large capital expense up front, but often a monthly charge based on a variable such as number of users or just a subscription. As a small company, the cloud is an attractive alternative to having to manage everything yourself and sometimes absorb the unforeseen costs of enterprise computing. In addition, you can add features through your provider that otherwise you'd have to buy and you would have to employ IT people who knew what to do. The downside can be that you want to highly customize your solution and your provider doesn't offer that without large costs. But if you're a small company, it's doubtful that will be a driver for you.

In regard to a private cloud, that's usually in the realm of large companies. It's an approach to their enterprise computing and they'll need IT people who are big picture. I hope that helps. You can also just type in "cloud computing" in Google and you'll see lots of good stuff.

Good luck.

John

Cloud computing is a term to mean that computing resources (applications, or servers or other resources) are shared (with other business entities) and acquired very quickly and easily, whilst being charged for what you use and no more (so you don't pay for a whole server and all the application license charges, but just for one user to use one service for the time you use it). So it's like paying for just the electricity that you use rather then paying for the power generators and the power cables etc. All the infrastructure cost is bundled up and shared between all the users of the service. You then choose to start using a little bit (turn on the switch), or to stop using your little bit (turn off the switch).
If I've just spent a whole paragraph telling you what your already know, then I apologise, but just wanted to set the context!
A public cloud is a service that is available to everyone and they all share the same infrastructure and services. Examples would be Google Mail and apps, Amazon Web Services etc.
A private cloud is usually a cloud that is built and used by the same company. This then takes away some of the benefits as the business then has to put in all the CAPEX and management resources to buy and support the infrastructure and applications. However once they accept that, they get much of the flexibilty of cloud services, but with all the compliance, business and security assurance they require.
It is often thought that a private cloud is a good option if you want to put your data or services into the cloud but don't want mitigate the risk of having the data in a shared environment with unknown controls and no service levels or responsibilities in protecting the service or data.
You may also be able to use another companies private cloud and thus ensure that sufficient contractual agreements are in place to protect your service and your data. This would be a half way house in that you would be sharing with limited user and have contractual agreements, but still have the flexibilty of cloud computing (including not having to build and maintain the infrastructure).

Hope this helps!

Hi Randy, Cloud computing is the buzzword of the year, and you're hearing a lot of phrases being tossed around. One of the clearest descriptions of cloud computing is here: http://www.youtube.com/watch?v=XdBd14rjcs0
This five minute animated video doesn't distinguish between private and public clouds, however. Generally speaking, larger clients are building private clouds because they have special considerations around data protection or because they have performance requirements that cause them to tightly control the infrastructure. Think of an organization like the US Department of Defense as an example: they have very special requirements and because of the large amount of compute resources they use, it makes sense for them to build a private cloud. As a small business owner, it is far more likely that a public cloud solution will be the most cost effective for you. As with all IT decisions, start with your business problem and work with someone who can map it to the appropriate IT solution.

Best wishes, Amy Anderson, Manager, IBM Cloud Initiatives for Partners

Good day, Randy:

This is my understanding of this rapidly changing and relatively new field.

A private cloud is one that is internal to the company that created it and maintains it.

http://www.dailyfinance.com/story/private-cloud-computing-companies-not-shari... might help in a general explanation of a private cloud.

http://www.youtube.com/watch?v=ZAbFR9A1XmY might help as well.

The private cloud implementation can still make use of outsourced companies; but the infrastructure is set up in such a way that the private cloud is limited to a specific customer.

A public cloud is akin to shared hosting in that the provider of a public cloud (say Amazon.com) is services multiple customers.

Thank you.

As other commenters have said, a small startup should not even think about private cloud. Instead, find the right software as a service (SaaS) providers for your particular needs.

For example, you can outsource email to Google (either Gmail or Google Apps) instead of running an in-house mail server. Doing so avoids the expense of internal hardware, system administration, backup, etc. Software as a service allows you to push all these costs back onto the service provider, which is the goal.

Another example might be SaaS-based office applications, such as word processing or spreadsheet. Rather than buy Microsoft Office, you might use Zoho products, Google apps, or Microsoft online products.

The common element is pushing infrastructure costs and labor from your company onto the external software as a service provider.

public is outside of entity network

This may help to explain it - http://www.circleid.com/posts/20090306_cloud_computing_types_public_hybrid_pr...

Hi Randy,

You've gotten some great answers above, so I hope my response is more clarifying than confusing.

You can't "buy" cloud computing, because cloud computing is really a delivery philosophy, or delivery model that says the end user should be in the driver's seat. Cloud computing is about enabling self-service and self-management for a "service" enabled by IT. An example of this is booking travel online - you're in charge and the systems and scope of what you access is based on the complexity of your trip. When you're done, the resources you used are allocated to someone else. Another example would be doing your banking via your smartphone. Both of these are "business or consumer based services" that are a cloud computing delivery model.

Most of the answers above were about one type of service that you could acquire from the cloud, IT computing resources, or "Infrastructure as a Service." However, starting out new with your own start-up, you may or may NOT want to manage at the infrastructure layer. That depends on your business. Because cloud computing is about a delivery model of services that are enabled by IT, it could be that you acquire your office applications from one provider, your CRM from another provider, your Finance and HR from a 3rd provider, and your companies web marketing from one of the others or even a 4th provider. The key to success is that you have an "architected" structure in place as to what services and resources you will need, and how they map together. In essence you create an enterprise IT architecture, it just may not be delivered from one place.

It really depends on how you want to structure it. the difference between "public" and "private" cloud computing is that the resources for a public deployment are fully shared with other companies and users in a full multi-tenant model. Google Apps or Gmail is an example. With a public cloud you pay for what you use, so they track your usage. Payment may be with money, but it may not. In the case of the example above, Google Apps and Gmail your payment is your "information", as everything that passes through Google's network also passes through their data mining software. Even if you "pay" for your Gmail account, it is still data mined.

A private cloud on the other hand is resources owned by you, and usually in your location, but the delivery of the resources is around self-service, self-management. Depending on the size of your start-up, this usually doesn't make a lot of sense.

Additional deployment options for cloud computing include "Managed Private Cloud", where the resources are under your control soley, but the solution is managed by a 3rd party, "Hosted Private Cloud" where the resources are hosted at a 3rd party site and may or may not be managed by you. There is also a modified version of a "public" cloud called "Shared Services", "Member Services" or "Community Services" cloud. Here you share resources with other people but you have to be a member of the community to get access to the services. An example of this would be IBM LotusLive, an email and collaboration solution for companies where you have to have an IBM customer ID to gain access to the services.

I know this has been a lot to take in, but you are on the right track. As a start-up organization you should look to limit your capital investment in an IT infrastructure if in fact it is better for you to "Pay as you Go" and have total control over how much or how little you use.

If you have any other questions, feel free to email me.

Many of these answers go into great detail and avoid just getting to the simple answer.

A private cloud is created when a server, which could be a virtual server, is set up to allow remote access via secure means, like a VPN. I would expect that the server would be in a data center somewhere, but I have heard at least one person insist that it could be in your office as well. Access is only given to those who have the proper credentials and is tightly controlled. At least one of the previous answers states that you would still have the CAPEX for this type of solution, but that isn't necessarily so. Many solution providers are offering this type of solution on a pay as you go basis.

A public cloud is not controlled by your organization. Examples of public clouds might be Google Apps or Salesforce.com. Access to your information is controlled, but the server resources are shared among different organizations and you don't have any control over how anything is configured or backed up.

After reading all this post, I got another idea, "How about a Cloud Tree?" Means I am using cloud service from a company and I can offer that service to another company and my parent company got also benefit from the same.

It's just an Idea, don't know, It is possible or not.

A Public cloud is also known as a shared cloud. Public cloud services are provided "as a service" over the Internet with little or no control over the underlying technology and infrastructure. This cloud is appealing to many decision makers as it reduces complexity and long lead-times in testing and deploying new products. It is generally cheaper, too.
A Private cloud is also known as an internal cloud or enterprise cloud. Private cloud services are also provided "as a service" over the Internet, but, such a cloud is deployed over a company intranet or hosted datacenter. This is private product for a company or organization offering advance security and highly available or fault tolerant solutions not possible in a public cloud. In this scenario, the private cloud owner shares few, if any, resources with other organizations. Hence, multi-tenancy is not an issue.
For more information, click here –
http://www.myrealdata.com/cloud-computing.html

Hi, Randy.

I work for GetApp.com and we have two contents that can be useful for you to understand the differences between public and private clouds.

1 - A question in our Q&A asking what are the main benefits of a private cloud (http://answers.getapp.com/Private-Cloud-What-main-benefits-q717.aspx). The answers are very relevant and explain very well, and with some links to extra content, what is a private cloud and its benefits.

2 - We also have an article in our blog written by Manuel Jaffrin, CoFounder of GetApp.com, explaining the basic differences between public and private cloud and presenting an infographic produced by Wikibon. (http://www.getapp.com/blog/public-cloud-vs-private-cloud-the-business-case-in...)

Sorry for not directly answering your question, but I thought it could be much more useful to point you to relevant content.

Regards,
Diego.

A cloud can be categorized into;

1. Public Cloud: A public cloud sells services to anyone on the Internet. (Currently, Amazon Web Services is the largest public cloud provider.) Applications, storage, and other resources are made available to the general public by a service provider. Public cloud services may be free or offered on a pay-per-usage model. There are limited service providers like Microsoft, Google etc owns all Infrastructures at their Data Center and the access will be through Internet mode only. No direct connectivity proposed in Public Cloud Architecture.

2. Private Cloud: A private cloud is a proprietary network or a data center that supplies hosted services to a limited number of people. Private cloud is infrastructure operated solely for a single organization, whether managed internally or by a third-party and hosted internally or externally. They have attracted criticism because users "still have to buy, build, and manage them" and thus do not benefit from less hands-on management, essentially "[lacking] the economic model that makes cloud computing such an intriguing concept".

Source: http://www.cloudreviews.com/

Actually, Randy, all of the above answers are somewhat incorrect. They are accurate in the public vs private cloud definitions, but where they have it wrong is that you, as a small business owner, CAN afford a private cloud solution.

My company, Insol - Intelligent Network Solutions, has been in the IT business for over 20 years. We have made it through the dot com crash, the evolution of the PC and developed our secure private Cloud solution 3 years ago. Recently, we developed a solution for the small office/home office owner call The S.O.H.O. Cloud Solution (one of our three Cloud solution offerings).

The S.O.H.O. Cloud Solution offers all of the large PRIVATE cloud solutions bells and whistles (disaster recovery, top notch security, file sharing, multiple office environments, virus protection, firewalls, etc) AND for all you techies (private vlan, access control lists, physical hard 2tb partitions, secure VPN tunnel) all housed in your private space in our Tier IV data center with 99.999% guaranteed uptime.

The brilliant piece of the Insol S.O.H.O. Cloud Solution is that it grows with your organization. If you start with 2 people today and have 20 in a year, we can easily migrate your data and applications to one of our larger Cloud solutions.

I invite you to contact me at lhurst@insolnet.com for more information on the small business owner's cloud solution. You never have to settle for a public cloud -- you can afford a private one.