Re: [mdnsext] mdnsext & SLP

Michael Sweet <> Sat, 22 June 2013 03:49 UTC

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From: Michael Sweet <>
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Date: Fri, 21 Jun 2013 23:48:59 -0400
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To: Garret Peirce <>
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Subject: Re: [mdnsext] mdnsext & SLP
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On 2013-06-21, at 11:27 PM, Garret Peirce <> wrote:
> ...
> It seems SLP is caches collected service advertisements whereas the mdsnext method demand polls for them.  

SLP with a DA caches, otherwise you have a similar amount of network traffic as for mDNS+DNS-SD.

> At the expense of somewhat less realtime data, caching advertised services would seem easier and more manageable than having proxies present on each subnet to manage the polling.  I'd not desire to operate the hybridProxy service on the subnet's router as a potential option it mentions; it'd seem unduly intensive for a router to assume that role (managing and caching queries, suppressing/rewriting others) - some other host would be required to assume this role on each subnet.

I don't know about that; based on discussions on the ipv6 list, even consumer routers have sufficient capacity to do some pretty advanced routing and other functions, so I don't think acting as a proxy or caching service is out of the question, particularly if the cache is not persistent or of "infinite" depth.

Michael Sweet, Senior Printing System Engineer, PWG Chair