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Re: [mdnsext] Wide Area DNS-Based Service Discovery walkthrough

Michael Sweet <msweet@apple.com> Thu, 14 March 2013 14:21 UTC

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From: Michael Sweet <msweet@apple.com>
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Date: Thu, 14 Mar 2013 10:21:43 -0400
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To: Michael Richardson <mcr+ietf@sandelman.ca>
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Cc: IETF mdnsext <mdnsext@ietf.org>
Subject: Re: [mdnsext] Wide Area DNS-Based Service Discovery walkthrough
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Michael,

On 2013-03-14, at 9:39 AM, Michael Richardson <mcr+ietf@sandelman.ca> wrote:
> 
> Thanks for that writeup.
> 
> Is there some way for an OSX box to learn what vendor specific printer drivers
> to load from SD?  I assume that OSX can also do the generic thing too?

Part of the whole discovery process gets the TXT record for the service which provides things like make-and-model, product string, etc.  OS X uses that to locate an appropriate driver.

Also in that TXT record is a priority for the protocol - LPD (_printer), AppSocket (_pdl-datastream), and IPP (_ipp) are the common ones.  OS X queries the TXT record for each of the supported print protocols and uses the priority value to choose which protocol to use. The priority value is set by the manufacturer and is sometimes available as a configuration option in the printer's web interface...

_________________________________________________________
Michael Sweet, Senior Printing System Engineer, PWG Chair

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