There’s been much debate about the relative merits of desktop applications versus Internet-based applications. Both styles have their advantages, but the hybrid of both is less reliable than either separately.
Hurricane Ike knocked out our electricity for a couple days. Once the power came back on, I could use any software installed on my PC. We don’t have an Internet connection yet, but I’ve been able to check email etc. from other computers. I can use my PC, I can access the Internet, but I can’t do both at the same time. That means, for example, I can’t add podcasts to my iPod. Also, my back-up software cannot run. Applications that require local software and an Internet connection are the least reliable. I can work locally and move files around with a flash drive, or I can work “in the cloud,” but I cannot work in mid-air.
The trend lately has been toward cloud computing, entrusting your data and applications to anonymous servers somewhere out on the Internet. This can be a smart move. Companies like Amazon and Google have more sophisticated contingency plans than most consumers: redundant power and network connections, data centers in multiple geographic locations, etc. But there are always trade-offs. Think about an analogous situation with utility lines.
There has also been a trend toward underground utility lines. And recent experience shows what a good move that can be. Essentially the only places in Houston that had power immediately after the hurricane passed through were Downtown and the Galleria, two areas with underground utilities. Everyone with above-ground utilities was in the dark. But there’s more to consider. When Tropical Storm Allison came through Houston a few years ago, the underground utilities flooded and Downtown was without electricity while areas with old-fashioned powerlines were OK.
Above-ground and underground power lines both have their advantages, and overall it seems the latter is better. The most vulnerable position would be to depend on both above-ground and underground utilities, analogous to depending on both a particular PC and an Internet connection.