Is going to "http://somewhere.com." faster?

[Mark_Andrews at isc.org]

> On Mon, 2 Aug 1999 Mark_Andrews at isc.org wrote:
> 
> } 
> } 	It is no longer "normal" behaviour and has not been for several
> } 	year.
> 
> Please explain the conditions under which this is abnormal behaviour.
> 
> } 	If your resolver has this behaviour it contains a significant
> } 	security flaw.
> 
> Again, please explain.  Only last week, I was looking into a resolution
> problem under BIND 8.2.1.  With the trailing ".", dig would resolve the
> name more quickly than without.

	Dig does *not* implement search list so it specifing a final dot
	will have had *no* effect.  nslookup and the resolver implement
	seach lists.  This is despite there being a seach arguement.

> 
> It would seem logical from the Bachus-Naur definition of a domain name
> that a fully-qualified domain name would include the null domain label for
> the root and therefore would be terminated by a ".".  Without a trailing
> ".", the resolvers would have only a partial domain name and would have to
> append the local domain to discover if this were a local domain name.

	Well if you have a resolver from BIND 8 or BIND 4.9.2 (or
	later) it will try the fully qualified name *first*.  If
	you specify a final dot it won't append the seach list
	*after* trying the name as is.

	Mark
> 
> Merton Campbell Crockett
> 
> 
> } > This is normal behavior of the resolver. And yes if you append a dot its 
> } > faster.
> } > 
> } > 
> } > >From: yong321 at yahoo.com
> } > >To: comp-protocols-dns-bind at moderators.isc.org
> } > >Subject: Is going to "http://somewhere.com." faster?
> } > >Date: Thu, 29 Jul 1999 16:20:55 GMT
> } > >
> } > >I'm learning DNS. At the nslookup> prompt, I "set debug". Then query
> } > >"www.uh.edu" for University of Houston (I work at Houston). It first
> } > >tries to find "www.uh.edu.mycompany.com" and gets 0 answers. Then it
> } > >tries to find "www.uh.edu" and finds it. Now if I type "www.uh.edu."
> } > >(with the appending dot), it finds it with one attempt. This is easy to
> } > >understand.
> } > >
> } > >Then I think if I go to the homepage of any Web site (not inside the
> } > >site), I can append a dot to the host name to speed up DNS lookup a
> } > >little bit. So in the browser, instead of typing the URL "www.uh.edu"
> } > >(or "http://www.uh.edu") I type "www.uh.edu.". Please comment. Thanks.
> } > >
> } > >Yong
> } > >Email:yong321 at yahoo.com
> } > >
> } > >
> } > >Sent via Deja.com http://www.deja.com/
> } > >Share what you know. Learn what you don't.
> } > >
> } 
> } > 
> } > ______________________________________________________
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> } > 
> } > 
> } --
> } Mark Andrews, Internet Software Consortium
> } 1 Seymour St., Dundas Valley, NSW 2117, Australia
> } PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org
> } 
> } 
> 
> 			     Merton Campbell Crockett
> +---------------------------------------------------------------------------+
> | Manager, Network Operations & Services | Senior Network/Security Engineer |
> | GTE Government Systems Corporation     |     Naval Surface Warfare Center |
> | Electronic Systems Division		 |            Port Hueneme Division |
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> 
--
Mark Andrews, Internet Software Consortium
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org