What does running software in the network mean exactly?
This is one of the questions that users are exploring as they start to increasingly poke at what "cloud computing" means for them.
On the one hand, cloud computing can refer specifically to running some sort of fixed software service--frequently through a browser's user interface--over the network. This is cloud computing in the Web 2.0 sense. We don't necessarily even think of Flickr, Facebook, or Google as "applications" as such. At the other end of the scale, services such as Amazon's EC2 and S3 just rent bare CPU cycles and storage capacity for whatever software a user wants to load up.
However, between these extremes lies a continuum of customization and malleability. Application programming interfaces that allow third-party customization and extension are rapidly becoming a de rigueur companion to software as a service. At the same time, virtual appliances and other predefined software loads offer at least a degree of preassembly when renting raw computing by the hour.
Tuesday's announcement by Mosso, a start-up funded by hosting provider Rackspace, offers up yet another variant. The core concept behind Mosso's Hosting Cloud is that many Web-based applications or sites are built up using largely common stacks of technologies such as PHP and MySQL databases. Mosso takes advantage of this fact by providing the means to provision applications running on one of these common stacks. Mosso is effectively offering cloud computing at a level of abstraction more akin to that of a Web hosting provider. For example, Mosso takes care of patching and updating the operating system and other software stack components. This is unsurprising given Rackspace's historical business, but it's a bit different than what's generally discussed in the context of cloud computing.
A user sets up a site by logging into Mosso's management application, entering a domain name, the technology stack to be used (Mosso supports Windows/.Net as well as Linux), and additional services required--such as databases. Mosso will then provision the site on a cluster of servers at which time the user can upload custom code.
The big difference from a typical hosted Web site is that Mosso monitors the site's resource use and will scale up available hardware resources as needed automatically. The pricing model is as follows:
Base pricing is $100/month, which includes:
- 24x7 live technical support (phone and chat)
- 50GB disk space
- 500GB bandwidth
- 3 million Web requests/month (A Web request is the retrieval of any item from a Web server, i.e. a Web page with two photos counts as three requests)
Additional disk space is 50 cents per gigabyte, bandwidth is 25 cents per gigabyte, and requests are 3 cents per 1,000 requests.
Mosso does not currently provide any means to throttle or otherwise limit the traffic or resource use by a site. This seems reasonable enough in the context of businesses that would typically be more concerned with their site going down than in having an unexpectedly large hosting bill at the end of the month. In addition, by partially pegging charges to Web requests, Mosso is aligning its fees to a measurement that has direct relevance to many companies operating Web sites--especially if they are advertising-supported in some way.
Writing Defining Cloud Computing last month really crystallized for me that it would be a mistake to narrowly define this trend as only about Web 2.0 or software as a service. Announcements such as Mosso further emphasize this point. More and more computing may go out into the network. But the way that it moves into the network will take a multiplicity or forms--especially as users experiment in these early days.