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Re: ID: Proxy autoconfig

From: Josh Cohen <josh@netscape.com>
Date: Thu, 27 Mar 1997 18:14:26 -0800 (PST)
To: "nemo/Joel N. Weber II" <devnull@gnu.ai.mit.edu>
Cc: dwm@xpasc.com, dmk@bell-labs.com, josh@netscape.com, http-wg@cuckoo.hpl.hp.com
Message-Id: <ML-3.1.859515266.5627.josh@birdcage>
> 
> I personally would rahter see dhcp used instead of dns I think.
> But I need to read the dhcp spec before I comment furthur...
There is a draft which recommends using dhcp instead, which I cite
in my draft.
I beleive the Server Location Method is a better choice because:

1. DHCP doesnt have a cross platform interface to its configuration
  option.  By using DNS, or even the raw SVRLOC multicast protocol,
  its still a consistent and relatively easy implementation.

2. DHCP is a one time configuration retreival, the proxy config can 
   change dynamically, and DNS allows a mechanism to do that.
	( ie it has a lifetime )
   ( yes, DHCP has a lease, but I beleive that is meant to be more
     long lived )

3. Service location is an appropriate way to advertise a service,
   which I beleive the proxy is.  The browser is discovering
   an available proxy service, not a host configuration option.

4. DNS is much more commonly deployed where the web clients are
	(its usually a necessity ), while DHCP seems to be mainly
 	popular on PCs

>   I think the default should be up to the client publisher. I would
>    recommend that once the user has manually altered setting, either those
>    setting persist or the user should be asked if the settings are
>    temporary. 
Agreed ( in previous reply )

> machines, I changed about three teacher's machines manually.  Those
> teachers didn't have a clue what a proxy is; and it would be no easier for
> them to tell the browser to use automagic setup than it is for them to
> say to use 204.130.130.62 port 80.
Yes, if thats all your saying, but these days, a common config would
be something like:
set http:// to go to proxy1 on port 80
set ftp:// to go to proxy2 on port 80
set https://*.evil.com to proxy 3 in port 443
set no-proxy for mydomain.com yourdomain.com thishost.thatdomain.com

and more complex ones are coming ie:
send HTTP GETS to proxy2 on port 80
send HTTP PUTS to proxy3 port 80.

I suspect that if the browser can detect this by itself, out of the box,
the teachers life is greatly simplified.

As an aside, even if the discovery isnt used, the teacher still
must navigate to 'proxy settings -> auto' and specifiy
the URL: http://proxy:8080/proxy.pac
which is still much easier than a manual configuration.

I want to make the point that as caches as being deployed
more frequently and with more complexity, ie hierarchies and
dynamic ICP type protocols, the configurations need to be
dynamic and complex.  Well beyond what a nontechnical user
should need to know, and extremely difficult to provide
a UI to let a user specify it manually.


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Josh Cohen				        Netscape Communications Corp.
Netscape Fire Department	               "My opinions, not Netscape's"
Server Engineering
josh@netscape.com                       http://home.netscape.com/people/josh/
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Received on Thursday, 27 March 1997 18:15:55 EST

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