Re: [mdnsext] mdnsext & SLP

Michael Sweet <> Fri, 21 June 2013 16:43 UTC

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From: Michael Sweet <>
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Date: Fri, 21 Jun 2013 12:43:34 -0400
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To: Garret Peirce <>
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Cc: IETF mdnsext <>
Subject: Re: [mdnsext] mdnsext & SLP
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On Jun 21, 2013, at 12:15 PM, Garret Peirce <> wrote:
> Michael,
> I had thought the purpose of an SLP DA was to enable SD across subnet boundaries.
> The idea being there could be a number of them setup for different reasons (ex. organizational/serviced scoped).
> ref: RFC2608 section 12.

*If* the DA spans the subnets, a single DA could service all of them and still be auto-detected by the UA's.  But that really only works for simple topologies where you have a common gateway or router joining the subnets.

If you use DHCP to set the DA for the UA's on each subnet, then you have to configure each of the DHCP servers to do that...  And you still have the issue of resolving hostnames and/or routing addresses for the services - for example, a printer might advertise its printer service with any of the following:


The only ones that are likely to be directly usable are the last two...

Michael Sweet, Senior Printing System Engineer, PWG Chair