[dnsext] stupid dns tricks and transport paths

Jim Reid <jim@rfc1035.com> Fri, 29 January 2010 10:35 UTC

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From: Jim Reid <jim@rfc1035.com>
To: Paul Vixie <vixie@isc.org>
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Subject: [dnsext] stupid dns tricks and transport paths
Date: Fri, 29 Jan 2010 10:31:27 +0000
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On 28 Jan 2010, at 21:41, Paul Vixie wrote:

> i've been told that because of stupid dns tricks, youtube sucks
> for people whose recursive dns doesn't share fate and path with  
> their tcp
> stack.  i'm just parroting what i've been told, without understanding.

I can't speak for youtube (whatever that is). However I can vouch from  
personal experience that stupid DNS tricks get it wrong, even when  
recursive DNS service and TCP traffic share the same path. English  
speakers can see this pretty much every time they connect to a hotel  
or coffee shop network in mainland Europe. The CDNs provide stuff in  
that country's national language -- good luck getting that right in  
Belgium or Switzerland -- rather than English. Similar problems arise  
in large corporate networks which have a small number of interconnects  
to the Internet: the CDNs decide the user is in Germany (say) because  
that's where the firewall or web proxy is located.