Cloud” is a 2008 buzzword to rival the “V” word above. On the storage side, everyone from IBM to EMC to Microsoft has weighed in with a strategy or offering regarding storing data in the server cloud.
This trend, though, may be more sizzle than steak.
“The idea of hosting all your applications and files ‘in the cloud’ and using a thin client as your main means of access to them will never take off,” argues Jon Stokes, senior editor and co-founder of Ars Technica. “I store quite a bit of data in my IMAP inbox via attachments, and I can access most of those files on my iPhone. So that’s a form of cloud-plus-thin client computing, I suppose. But I’m not going to work an eight-hour day that way.”
Though Ontario’s privacy commissioner has been probing the security and privacy aspects of the cloud, Stokes says latency is the bigger challenge. There’s an unchangeable inverse relationship between latency and cost per bit, and the cloud doesn’t change that.
“Computer designers always place the maximum amount of the lowest-latency storage that they can afford as close to the ALUs as they can get it,” he says. “Economics dictate that that maximum amount is never really enough to do everything you want to do, so they have to back that low-latency storage pool up with a larger, cheaper, higher-latency pool. And then they back the new pool up with an even larger pool, and so on until you get very far away from the ALUs.”
Most of our work takes place in the layers of that hierarchy that are closest to the processor: the computer’s hard disk, out to file servers on the local area network and the data centre. The cloud just provides more cheap, high-latency storage much further down in the hierarchy.
“That bottom, very cheap/slow layer is useful, but when you start suggesting that people will cut out the middle layer and spend a ton of cycles waiting for data to go back and forth between main memory and some distant networked storage device, then you’re just talking nonsense.”
That said, the Web services market will take it seriously – it’s not that latency-sensitive – and consumers and the enterprise use it for backup and document sharing, Stokes says.
