Differences between SaaS and Cloud Software

With all the discussions about about Cloud Computing going on, it’s time to draw lines and explain what the big differences are between Software-as-a-Service (SaaS) and Cloud Software.cloud-jail.jpg

SaaS: The dawn of Cloud Computing

SaaS has been attractive, because it removes all complexity from installation, deployment, maintenance, is globally accessible, and affordable. By its nature, SaaS resides in the “cloud” and overcomes the traditional headaches of VPNs for efficient collaboration. An added bonus is transparent backups (assuming there is backup strategy).

SaaS is great first step towards Cloud Computing, but it also has an important drawback: control. For all practical purposes, your data is not yours anymore. The SaaS vendor has full control over it; can mine it; and can lock you out of it. For consumers, this is generally

In short with SaaS, the vendor is in control, not the customer. For the early days of Cloud Computing, that was an acceptable compromise, but times have changed and the cloud has evolved.

Cloud Software: The evolution of Cloud Computing

Cloud Software builds on Cloud Infrastructure (as described in this great post by our friends at RightScale). Similar to SaaS, Cloud Software provides instant gratification, taking mere minutes to be up and running. Depending on the vendor, Cloud Software is as easy to maintain and update as SaaS, and is of course globally accessible.

So what is the big difference? Your data and your application is sitting on servers that you control. There are no restrictions on moving data into or off your Cloud Infrastructure. These servers are for all practical purposes indistinguishable from servers in your physical data center.

What about backups? Cloud Software is designed to be run in the cloud. That means, it already addresses the need to replicate data repositories into the Cloud Storage fabric. Again, you control the Cloud Storage, so you can create additional copies of your data offline if you need to.

What about scaling? Cloud Software is designed to run on one to many machines. That means as your needs increase, you simply add more virtual infrastructure to the mix and voilà!

What about vendor lock-in? Cloud Software doesn’t really care what it runs on. With Cloud Infrastructure, all machines look the same, meaning you can move your application from one provider to another with few limitations. If need be, you can even move it back to your physical data center.

In short, with Cloud Software, the customer is back in control.

Is Cloud Software going to replace SaaS?

The short answers is “no” for the simple reason that SaaS works well when a single machine can services 1,000 to 100,000s of individual users, such as in a consumer setting. In the enterprise, however, Cloud Software has a big advantage. The premium to gain full control over your data and your infrastructure with Cloud Software is simply too low to give SaaS vendors the kind of control they have enjoyed so far. High value applications will transition to Cloud Software because customers want control, while SaaS will continue to supply free or low-cost applications and services.

This also reflects the different options for running MindTouch Deki Wiki. Wik.is is free for up 100MB (or $99/yr for 10GB) with no other restrictions, but the data reside on our servers. Alternatively, you can download Deki Wiki as a certified VMware image or from source code and install it on your servers. Or, you can get the best of both worlds, and launch a Deki Wiki EC2 instance directly in an Amazon.com data center in the cloud

It’s good to have choices!

http://www.mindtouch.com/blog/2008/05/28/differences-between-saas-and-cloud-software/