I've just returned from Madison, Wisc., where I worked with the good folks at WiscNet, the state research and education network provider, to conduct a look at three DNS (Domain Name System) appliances. WiscNet is considering appliances to replace its aging DNS implementation.
At one point in the post-event wrapup, one attendee--a representative of a Midwestern state net--asked, "Who here tried e-mail appliances and then stopped?" His point was that appliance solutions, for his organization, hadn't worked out that well. In fact, he shared that after only a year of operation, he was in the midst of replacing his e-mail appliances.
It made me think that this was a valid concern for small and midsize companies, whereas many large organizations like the appliance model, or so I've been told, because it compartmentalizes the installation and maintenance process in a way that is easier to deal with in a large bureaucracy.
I think the spirit of the question arose, however, from the notion that "software on a server" (SOAS?) isn't dead yet. I think the next thing to ask is, "Will it virtualize?" In other words, would DNS running on a virtualized Linux host work well enough to provide the kind of nonstop service that is needed by an organization like WiscNet? If not, then it just might signal the rise of the appliance.