As you likely know, the DNS is the network function that translates domain names (like www.nwfusion.com) to IP addresses (like 65.214.57.165).  And though this service is sometimes supplied a few organizational steps away from corporate telecommunications, it still has a profound impact on perceived network reliability.

For instance, if a user asks his browser to go to www.ebay.com and gets the infamous "page not found" message, the user considers this a network failure.  The fact that your physical layer all the way through your IP network might be working fine is seldom, if ever, apparent.  All users know is that they can't get to the eBay site - even though they might have been successful had they entered http://66.135.192.87/.

One mode of thinking, as Web sites and, in fact, virtually all corporate network services become increasingly dependent on DNS services, is that DNS is becoming a core network service like routing or switching. As such, perhaps DNS should move away from general-purpose servers, often managed by multiple internal groups, and into a more reliable form factor that is easier to secure and manage. This could minimize service downtime.

Historically, as pointed out in a recent article posted at Webtorials, "The DNS Appliance Imperative," authored by DNS aficionado Cricket Liu, vice president of architecture at Infoblox, various networking functions have moved from general-purpose processors to dedicated appliances.  One of the most dramatic instances of this is the router.  Originally, in the infancy of the Internet, routing took place in a network interface inside a Unix workstation.  However, as the routing market matured, one achieved higher performance at a lower price with specialized systems purpose-built for routing.

In more recent years, we've seen this same approach applied to traffic management gear and firewalls.  So perhaps it makes sense to move DNS to a specialized appliance, as well.

Hint:  Want to know exactly how often your perceived network failure is a DNS failure?  Find out the IP address of a few network sites that you frequent, and do a "ping" of the site to determine the IP address.  Next time the site is "down," try entering the IP address of the site rather than the domain name.  Odds are pretty good that you'll get a response.

Steve Taylor is president of Distributed Networking Associates and publisher/editor-in-chief of Webtorials. Jim Metzler is vice president of Ashton, Metzler & Associates.