Hi, Maybe this links will help :
https://blog.cloudflare.com/dns-resolver-1-1-1-1/ https://blog.cloudflare.com/announcing-1111/ Best regards. > Le 1 avr. 2018 à 19:05, Mike Hammett <[email protected]> a écrit : > > Unless you want optimum CDN performance, then your recursive servers belong > pushed back in your network until there are no more diverse upstream\peer > paths to choose from. > > Yes, I know there's an extension to DNS to help remove this need, but until > that's universally supported, you can't abandon the old way. > > > > > ----- > Mike Hammett > Intelligent Computing Solutions > http://www.ics-il.com > > Midwest-IX > http://www.midwest-ix.com > > ----- Original Message ----- > > From: "Stephen Satchell" <[email protected]> > To: [email protected] > Sent: Sunday, April 1, 2018 11:22:10 AM > Subject: Re: Yet another Quadruple DNS? > >> On 04/01/2018 08:18 AM, Matt Hoppes wrote: >> Why not just implement recursive cache severs on end user routers? >> Why does an end user CPE need to query one or two specific DNS >> servers? > Recursive lookups take bandwidth and wall time. The closer you can get > your recursive DNS server to the core of the internet, the faster the > lookups. This is particularly true of mobile and satellite. > > Implementing large caches in that close-to-the-core DNS server can add > another benefit: lookups to common and popular endpoints, such as > Google, would require far less real time to resolve. As the traffic > tides change, the cache would change with it, so flash-in-the-pan sites > would be served from cache, and forgotten in time when said sites drift > back to obscurity. > > (I wonder if the Internet Systems Consortium has considered adding a > cache-hit counter, or even a very coarse heat map (say, four 16-bit > counters cycled every five minutes), to DNS entries, to figure out the > best ones to drop? It would increase the complexity of BIND, but the > benefit for a BIND server serving a largish customer population could be > significant. If I were younger, I might try to model such a change. > Sort by hits, then by time-to-die. Drop the oldest 250 or so entries > when the cache is full. That way, the oldest least-used cache entries > get dropped.) > > ISPs provide to their customers DNS addresses to servers that, > allegedly, are closer to the core than the customers are. (Pipe dream, > I know; which is why so many ISPs have decided to specify 8.8.8.8 and > 8.8.4.4, because Google is closer to the core than the ISP is.) > > I've not personally measured the number of times a look-up could be > satisfied from a cache in a production environment; it's been 15 years > since I worked in such a job. It would be interesting to see if someone > has taken the time to gather those statistics and published them. > > The main reason for *not* implementing recursion exclusively in CPE is > that a recursive lookup is a complex operation, and I have my doubts if > BIND or equivalent could be maintained properly in, say, a wireless > access point (router) -- how would you update a hints table? >
