Fancy uploading a terabyte of data?

What would you do if you ran an online backup service that offered unlimited storage, and a few dozen of your customers ended up storing more than a terabyte of data each?

Carbonite CEO David Friend decided to take a softly, softly approach, e-mailing each of the high-volume users to let them know of their unusual status.

Given that one of the selling points for Carbonite is unlimited storage, Field couldn't exactly say "You so-and-sos are breaking the rules". The responses Field got, according to Carbonite's international VP Floyd Bradley, were mixed.

Quite a few customers sent back a variant of "I wondered when you'd find me", while some simply didn't respond -- Bradley hypothesises that some were competitors simply uploading reams of data to see what would happen.

Bradley was in Australia to launch the local version of Carbonite -- AU$59.95 a year for all the data you can upload, automatically backed up from a Windows machine. To be honest, local customers are unlikely to approach that terabyte figure, if only because most Australian ISPs enforce caps on the amount of data that can be transferred, and an increasing number include uploads as well as downloads in that total.

Carbonite's own research suggests that the average user backs up less than 20GB, a fair whack given that the service covers individual documents rather than software. But even 20GB is greater than the monthly allowance on most local broadband plans -- while the ongoing backup is incremental and compressed, it all still has to get into Carbonite's Boston datacentre in the first place.

There's a couple of possible solutions. The software can be set to back up at certain hours, which is useful if your ISP offers discounts for use overnight, when networks are less cramped. Carbonite's local distributor, Avalanche Technology Group, is engaged in discussions with local ISPs to get the service zero-rated -- so it is not counted towards the monthly cap -- but no deals have yet been signed.

Given that most individuals are absolutely slack about backup, rejecting an automated solution purely because of data costs is pretty stupid. Even setting the service to back up your My Pictures folder could save a lot of tears.

There's also a lesson here for corporate datacentre managers. Remote backup is an essential strategy for any moderately sized business but transfer costs are going to be a major factor. Your budget might be higher than the average consumer, but your boss is probably nastier too.