[dns-operations] Behavior of browsers with absolute HTML links (Was: compressing

[Joe Greco]

> On Wed, Dec 08, 2010 at 09:17:03AM -0600,
>  Joe Greco <jgreco at ns.sol.net> wrote 
>  a message of 57 lines which said:
> 
> > Back in the infancy of the Web, relative links were king, and some
> > web pages only generated one DNS lookup to enable the page to load,
> > and many other pages only had at most a handful.
> > 
> > By today's count, and I did just count, pulling up www.ebay.com
> > results in *204* lookups, www.cnn.com results in 92 lookups,
> > Facebook 24, etc.  That's actual requests happening on the wire per
> > tcpdump.  (I'm actually a bit shocked.)
> 
> What is the behaviour of a Web browser when there are several
> *asbolute* links with the same "prefix"? I would have assume that two
> links <http://www.example.org/foo.html> and
> <http://www.example.org/bar.html> create only one DNS request?

Links shouldn't generate DNS requests simply for existing, but
other fetches such as images do.  I'm guessing that's what you
mean.

So something like

http://www.sol.net/test/bortzmeyer-absolute-url-dns-lookup.html

Yeah, it's only supposed to generate one lookup for www.sol.net
and the application ought to cache that for a bit.  Although it
is interesting, it worked that way on initial load, but upon a
click on "reload" it generated three requests (I have no idea
where *three* would be coming from, two or thirteen might make
sense given the data on the page).

Or did you mean when clicking on a link in a page?  In my 
experience, that'll happily use the existing cached data.

... JG
-- 
Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN)
With 24 million small businesses in the US alone, that's way too many apples.