Earlier, William Herrin wrote: % And, it also presupposes that DNS servers/resolvers % for root, TLDs (especially arpa), and reachable destinations, % will be available 100% of the time.
This raises a separate point which maybe is worth repeating. The overwhelming majority of users/deployments today are unable to distinguish "DNS service unavailable" from "network down". I first learned this while working in network engineering for a multi-continent residential broadband ISP in the latter half of the 1990s. It has been reinforced repeatedly since then when I talk with network engineering/operations folks at various other ISPs around the globe. Just to be clear, those ISP folks consistently say that this user inability to distinguish "network down" from "DNS service unavailable" applies to all sorts of users: residential, commercial, enterprise, academic/educational, government, military, and everyone else. So, for the overwhelming majority of users today, a DNS fault is viewed as being identical to a hard network fault (such as a fibre cut or power failure). I think this means that being more explicitly reliant on DNS service availability now, versus 20 years ago, is widely acceptable. Cheers, Ran -- to unsubscribe send a message to [EMAIL PROTECTED] with the word 'unsubscribe' in a single line as the message text body. archive: <http://psg.com/lists/rrg/> & ftp://psg.com/pub/lists/rrg
