[X4U] Re: Leopard Issues - Some Responses

Craig A. Finseth fin at finseth.com
Tue Dec 4 05:53:37 PST 2007


	...
   4) The issue isn't how Verizon handles a poorly formed URL.
   Domain-guessing adds the www and the dot com, so the
   ISP sees a correctly formatted URL. I get the Verizon-Yahoo
   search engine because the browser sends the incomplete URL
   (the way I typed it).

Domain guessing failures can be an interaction of both the browser and
the ISP.

Essentially, it works something like this:

- you enter "fred"
- the browser looks it up as you entered it
- if it finds an A record, successs!
	> of course, this may be the A record of the ISP search page: BAD!
- otherwise, it looks to see if there is a "www" prefix and/or "com" suffix
(the exact list varies among browsers)
- it then looks up that name

With the ISPs confusing things, the browser has to now determine
whether an "apparently successful" response is due to true success or
a false success.  So, we're now in an escalating arms race here.
Thus, erratic results.

Craig


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