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Re: (DNS) draft wording for W.G. review.

From: <hallam@w3.org>
Date: Wed, 27 Mar 96 14:08:11 -0500
Message-Id: <9603271908.AA14259@zorch.w3.org>
To: Anawat Chankhunthod <chankhun@catarina.usc.edu>
Cc: hallam@w3.org, http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com

>- dns is a real performance pain
>- gethostbyname call doesn't give you ttl information back
>  So, if a ttl info is needed, you have to basicially integrate all 
>  resolver code, talking udp to DNS server. Also server selection, timing out,
>  exponential back off and all that. Basically, it is a integration of the 
whole
>  BIND into client/server.

Gethostbyname is not rocket science. Its a few UDP calls and a bit of unpacking. 
It should not be very hard. I wrote an interface in a couple of days. 

Not using the Berkley interface is an obvious thing to do to improve performance 
if you do not have threads. It is a bit sad that Netscape hangs while waiting to 
do a dns lookup.

I don't think we should restrict the spec on the basis of an inadequate API to 
what is only a few lines of code. The complexity of BIND lies in the server not 
in the client. Anwat's post pretty much describes what one has to do.

Note that there are some platforms where it is difficult to interface directly 
to the bind daemon because someone has tried some half baked optimisations. I 
remember when we used to ship libwww with two versions of code, one for the 
people using the O/S version and the other (and by far the more widely used) 
which used a direct interface to dns. I don't know whether that is still an 
issue.


If people like I will post the code [just don't clutter the list with requests 
or JG will be upset]. It may requires some tweaks since I use a garbage 
collector and a few layers of macros, I think its only about 100 lines of code 
though].

	Phill
Received on Wednesday, 27 March 1996 11:12:30 EST

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