In an apparent bid to lure back those customers who've made the switch to OpenDNS (along with those users' DNS redirection ad dollars), Comcast this month announced in our forums that they've launched a new portal for tracking DNS server uptime. "The new DNS cache query tool will allow customers to run queries against not only our National Domain Helper cache servers but also the No Redirect caching servers as well," says a Comcast employee. "You can also run a custom query against other third party DNS servers," they note.

It's a welcome change, given both the DNS and network status pages for most major ISPs are either non-existent or leave plenty to be desired. According to the company, improved functionality will be added to the website in the coming months.

In July Comcast became the latest ISP to employ DNS Redirection advertising, which replaces the traditional 404 page with an ad-laden search portal that pops up when a user mistypes a URL. The practice essentially creates an entirely new revenue stream out of clumsy typists.

While such services aren't popular among 'Net purists and are over hyped by carriers as being more helpful than they really are, Comcast at least went about deploying it the right way by making it easy to opt-out of, engaging in clear dialog with our users, and standardizing the practice transparently with the IETF. Many ISPs have lunged dumbly for the advertising cash without ensuring their opt-out mechanisms even work.

Given the popularlity of alternative DNS services like OpenDNS, it's not too surprising to see ISPs start giving DNS functionality a little more attention. Flaky DNS servers for the major ISPs consistently act to give OpenDNS free advertising, and the company cashes in: in 2008 it was estimated that OpenDNS generates a whopping $20,000 per day off of their DNS redirection relationship with Yahoo. ISPs obviously want to keep that money in house.