What cloud computing really means

Cloud computing is all the rage. "It's become the phrase du jour," says Gartner senior analyst Ben Pring, echoing many of his peers. The problem is that (as with Web 2.0) everyone seems to have a different definition.

As a metaphor for the Internet, "the cloud" is a familiar cliché, but when combined with "computing," the meaning gets bigger and fuzzier. Some analysts and vendors define cloud computing narrowly as an updated version of utility computing: basically virtual servers available over the Internet. Others go very broad, arguing anything you consume outside the firewall is "in the cloud," including conventional outsourcing.

Cloud computing comes into focus only when you think about what IT always needs: a way to increase capacity or add capabilities on the fly without investing in new infrastructure, training new personnel, or licensing new software. Cloud computing encompasses any subscription-based or pay-per-use service that, in real time over the Internet, extends IT's existing capabilities.

Cloud computing is at an earlystage, with a motley crew of providers large and small delivering a slew of cloud-based services, from full-blown applications to storage services to spam filtering. Yes, utility-style infrastructure providers are part of the mix, but so are SaaS (software as a service) providers such as Salesforce.com. Today, for the most part, IT must plug into cloud-based services individually, but cloud computing aggregators and integrators are already emerging.

InfoWorld talked to dozens of vendors, analysts, and IT customers to tease out the various components of cloud computing. Based on those discussions, here's a rough breakdown of what cloud computing is all about:

1. SaaS

This type of cloud computing delivers a single application through the browser to thousands of customers using a multitenant architecture. On the customer side, it means no upfront investment in servers or software licensing; on the provider side, with just one app to maintain, costs are low compared to conventional hosting. Salesforce.com is by far the best-known example among enterprise applications, but SaaS is also common for HR apps and has even worked its way up the food chain to ERP, with players such as Workday. And who could have predicted the sudden rise of SaaS "desktop" applications, such as Google Apps and Zoho Office?

2. Utility computing

The idea is not new, but this form of cloud computing is getting new life from Amazon.com, Sun, IBM, and others who now offer storage and virtual servers that IT can access on demand. Early enterprise adopters mainly use utility computing for supplemental, non-mission-critical needs, but one day, they may replace parts of the datacenter. Other providers offer solutions that help IT create virtual datacenters from commodity servers, such as 3Tera's AppLogic and Cohesive Flexible Technologies' Elastic Server on Demand. Liquid Computing's LiquidQ offers similar capabilities, enabling IT to stitch together memory, I/O, storage, and computational capacity as a virtualized resource pool available over the network.

3. Web services in the cloud

Closely related to SaaS, Web service providers offer APIs that enable developers to exploit functionality over the Internet, rather than delivering full-blown applications. They range from providers offering discrete business services -- such as Strike Iron and Xignite -- to the full range of APIs offered by Google Maps, ADP payroll processing, the U.S. Postal Service, Bloomberg, and even conventional credit card processing services.

4. Platform as a service

Another SaaS variation, this form of cloud computing delivers development environments as a service. You build your own applications that run on the provider's infrastructure and are delivered to your users via the Internet from the provider's servers. Like Legos, these services are constrained by the vendor's design and capabilities, so you don't get complete freedom, but you do get predictability and pre-integration. Prime examples include Salesforce.com's Force.com, Coghead and the new Google App Engine. For extremely lightweight development, cloud-based mashup platforms abound, such as Yahoo Pipes or Dapper.net.

5. MSP (managed service providers)

One of the oldest forms of cloud computing, a managed service is basically an application exposed to IT rather than to end-users, such as a virus scanning service for e-mail or an application monitoring service (which Mercury, among others, provides). Managed security services delivered by SecureWorks, IBM, and Verizon fall into this category, as do such cloud-based anti-spam services as Postini, recently acquired by Google. Other offerings include desktop management services, such as those offered by CenterBeam or Everdream.

6. Service commerce platforms

A hybrid of SaaS and MSP, this cloud computing service offers a service hub that users interact with. They're most common in trading environments, such as expense management systems that allow users to order travel or secretarial services from a common platform that then coordinates the service delivery and pricing within the specifications set by the user. Think of it as an automated service bureau. Well-known examples include Rearden Commerce and Ariba.

7. Internet integration

The integration of cloud-based services is in its early days. OpSource, which mainly concerns itself with serving SaaS providers, recently introduced the OpSource Services Bus, which employs in-the-cloud integration technology from a little startup called Boomi. SaaS provider Workday recently acquired another player in this space, CapeClear, an ESB (enterprise service bus) provider that was edging toward b-to-b integration. Way ahead of its time, Grand Central -- which wanted to be a universal "bus in the cloud" to connect SaaS providers and provide integrated solutions to customers -- flamed out in 2005.

Today, with such cloud-based interconnection seldom in evidence, cloud computing might be more accurately described as "sky computing," with many isolated clouds of services which IT customers must plug into individually. On the other hand, as virtualization and SOA permeate the enterprise, the idea of loosely coupled services running on an agile, scalable infrastructure should eventually make every enterprise a node in the cloud. It's a long-running trend with a far-out horizon. But among big metatrends, cloud computing is the hardest one to argue with in the long term.

TECHNOLOGY CLOUD STORAGE SERVICES

As cloud technology has rapidly come on to the market, there are a few services that have stood out based on quality of services, integration with existing apps as well as quantity of space provided. Here are few of the best cloud technology services available right now.

1. DropBox

DropBox is a popular cloud service that isn’t backed by one of the big boys (Apple, Microsoft or Google).  It has a simple interface and it integrates with PC, MAC, iPhone/iPad, Android as well as Blackberry. A very nice feature that I use on my Android phone is an automatic picture upload to DropBox. No need for a card reader or USB cable. It just magically appears in a folder on my PCs….all 4 of my PCs and a MAC laptop. I can easily share what I have uploaded by simply sending an email through the various DropBox interfaces on each device or the DropBox.com website.

Downside: Starting Space

The starting amount of space, 2GB, is low compared to the other services BUT DropBox gives you several methods of getting more space like referring a friend for and extra 500mB. You can gain another 16GB by performing rather simple tasks to spread the gospel of Dropbox.

2.  Apple iCloud

Apple iCloud is Apple’s solution for all things Apple. The predecessor of iCloud was MobileMe that was used to sync e-mail, contacts, calendars, browser bookmarks, photo galleries and Apple iWeb and iDisk services. With the migration to iCloud, Apple added 5GB for free and more flexibility. This service ensures that all of your Apple devices (as well as PC) are synced. Space increases start at 10GB more for $20/year to 100GB for $100/yr.

Downside: Tailored for Apple

Unlike DropBox, iCloud isn’t going to seamlessly sync with your Android or Blackberry device very easily. But if you are and Apple only type, this is definitely the way to go.

3. Google Drive

Google Drive has a large 15GB starting space right out of the gate. It syncs with all of the major devices and is backed by a strong company that knows a thing or two about servers. Pricing for extra storage starts at $5/month for 100GB. The large starting space will be plenty for pictures and basic uses for most users. For the heavy users, the pricing is very reasonable. Google Drive syncs very well with other Google applications like Docs, Spreadsheets, Presentations and Drawings.

Downside: Large Gap in Pay For Space

This might be nit-picking, but the jump from 15GB to 100GB seems too big. DropBox does allow for ways to increase free space….but we also have to keep in mind that free space is capped at 18GB. Google Drive just gives you the space upfront without having to be an evangelist for the service. So…..Google Drive is strong all around.

4. Microsoft SkyDrive

Microsoft’s contribution in the cloud storage game is SkyDrive. It, like iCloud and Google are especially suited for Microsoft’s Windows Phone as well as the new Windows 8. Other devices can use SkyDrive but the integration isn’t as clean and easy. If you have have a Windows Phone, don’t look any further because this is the only cloud storage you can use. SkyDrive is very reasonably priced with 7GB free with your Microsoft Outlook account and you can add 20GB for $10/year.

Downsides: Compatibility

First of all…SkyDrive doesn’t give support to Windows XP. This seems counter intuitive but, for all of us that like that secure feeling of having an XP machine running those legacy programs. If Microsoft won’t support their own program on their own product, it will be a wonder if they give much thought in making it run on other company’s devices and platforms.