dslreports logo
site
    All Forums Hot Topics Gallery
spc
Search Topic:
uniqs
16
share rss forum feed

jjeffeory

join:2002-12-04
USA

1 edit
reply to guppy_fish

Re: Horrible youtube speeds

Huh?
DNS has nothing to do with "routing".
DNS resolves IP addresses with domain names. There is no need to use VZ DNS servers unless you want to allow Verizon to send you to whatever pages they want you to see.



rchandra
Stargate Universe fan
Premium
join:2000-11-09
14225-2105

Not necessarily. Your answer assumes a DNS server is a simple database; the same query always yields the same result(s). Many DNS servers work that way, but they don't have to. Just as long as the server follows the DNS protocols, it is free to give any answer it wishes to queries. In the case of large-scale operations like Facebook or YouTube, often the DNS server wishes to respond with AAAA or A RRs which, network-wise, are closest to the client. So for example, if I use OpenDNS's servers, their servers are simply going to forward the query along to one of ns1 - ns4 .google.com. The key difference is the source IP address will be of OpenDNS's servers, not your address. The answer may be optimized for OpenDNS's network, but not your slice of the Internet. So let's say just for the sake of argument you're in NYC and OpenDNS's servers are in LA. The answer back from ns1.google.com may assume you're on the west coast and hand out an address of a content delivery server close to LA. Then you'll be sucking the content clear across the US and be slow, when instead there's probably a duplicate content delivery server right in your own city and be zippy as all get out.

Depending on how YouTube's DNS programming goes, using Verizon's DNS servers in that case might be optimal. It may be even more optimal if you run your own recursive, caching DNS server. Then all the queries will have a source address of you and not Verizon's DNS servers.
--
English is a difficult enough language to interpret correctly when its rules are followed, let alone when a writer chooses not to follow those rules.

Jeopardy! replies and randomcaps REALLY suck!