Stormy Weather: 7 Gotchas in Cloud Computing
Costs, Part II: Cloud Storage Providers
Storage in the cloud is another hot topic, but it's important to closely evaluate the costs, says George Crump, founder of Storage Switzerland LLC, an analyst firm that focuses on the virtualization and storage marketplaces.
At about 25 cents per gigabyte per month, cloud-based storage systems look like a huge bargain, Crump says. But although Crump is a proponent of cloud storage, the current cost models don't reflect how storage really works, he says. That's because traditional internal storage systems are designed to reduce storage costs over the life of the data by moving older and less-accessed data to less-expensive media, such as slower disk, tape or optical systems. But today, cloud companies essentially charge the same amount "from Day One to Day 700," Crump says.
Amazon's formula for calculating monthly rates for its S3 cloud storage service is based on the amount of data being stored, the number of access requests made and the number of data transfers, according to Methvin. The more you do, the more you pay.
Crump says that with the constant decline of storage media costs, it's not economical to store data in the cloud over a long period of time.
Cloud storage vendors need to create a different pricing model, he says. One idea is to move data that hasn't been accessed in, say, six months to a slower form of media and charge less for this storage. Users would also need to agree to lower service levels on the older data. "They might charge you $200 for 64G the first year; and the next year, instead of your having to buy more storage, they'd ask permission to archive 32G of the data and charge maybe 4 cents per gigabyte," Crump explains.
To further drive down their own costs and users' monthly fees, providers could store older data on systems that can power down or off when not in use, Crump says.
Sudden Code Changes
With cloud computing, companies have little to no control over when an application service provider decides to make a code change. This can wreak havoc when the code isn't thoroughly tested and doesn't work with all browsers.
That's what happened to users of Los Angeles-based SiteMeter Inc.'s Web traffic analysis system this summer. SiteMeter is a software-as-a-service-based (SaaS) operation that offers an application that works by injecting scripts into the HTML code of Web pages that users want tracked.
In July, the company released code that caused some problems. Any visitor using Internet Explorer to view Web pages with embedded SiteMeter code got an error message. When users began to complain, Web site owners weren't immediately sure where the problem was.
"If it were your own company pushing out live code and a problem occurred, you'd make the connection," Methvin explains. "But in this situation, the people using the cloud service started having users complaining, and it was a couple of hours later when they said, 'Maybe it's SiteMeter.' And sure enough, when they took the code out, it stopped happening."
The problem with the new code was greatly magnified because something had changed in the cloud without the users' knowledge. "There was no clear audit trail that the average user of SiteMeter could see and say, 'Ah, they updated the code,' " Methvin says.
Soon after, SiteMeter unexpectedly upgraded its system, quickly drawing the ire of users such as Michael van der Galien, editor of PoliGazette , a Web-based news and opinion site. The new version was "frustratingly slow and impractical," van der Galien says on his blog.
In addition, he says, current users had to provide a special code to reactivate their accounts, which caused additional frustration. Negative reaction was so immediate and intense that SiteMeter quickly retreated to its old system, much to the relief of van der Galien and hundreds of other users.
"Imagine Microsoft saying, 'As of this date, Word 2003 will cease to exist, and we'll be switching to 2007,' " Methvin says. "Users would all get confused and swamp the help desk, and that's kind of what happened."
Over time, he says, companies such as SiteMeter will learn to use beta programs, announce changes in advance, run systems in parallel and take other measures when making changes. Meanwhile, let the buyer beware.