Fwd: Re: Server issues

Scott Kitterman ubuntu at kitterman.com
Wed Nov 21 00:48:20 UTC 2007

On Tuesday 20 November 2007 17:18, Neal McBurnett wrote:

> I haven't really caught up over the last 18 months with what has
> happened in the big IETF debates about mDNS (so-called "Apple") vs
> LLMNR (Link-local Multicast Name Resolution - so called "Microsoft").
> But I haven't heard that there is anything on the road to
> standardization.
> RFC 4795 was published http://tools.ietf.org/html/rfc4795
>  Link-Local Multicast Name Resolution (LLMNR)
> but that is just an "Informational" RFC, and just about anyone who is
> persistent enough can get one of those published.
> Security issues have been identified with both of them,
> since they let systems mess with names that look like
> official dns names.
> I find a lot of appeal to finding a good standard for simplified
> configuration, like zeroconf.  But I think that it is a difficult
> thing to get right :-(
The IESG note covers it pretty well (at least at a high level):


   This document was originally intended for advancement as a Proposed
   Standard, but the IETF did not achieve consensus on the approach.
   The document has had significant review and input.  At time of
   publication, early versions were implemented and deployed.

The lack of consensus (anyone can search the IETF main list for the last call 
discussion on this RFC, it was pretty extensive) was primarily over whether 
to use the mDNS or LLMNR protocols in the .local namespace.  Informational or 
not, it's a published RFC.  The distinction among Informational, 
Experimental, and Proposed Standard is significant within the IETF community, 
but in the wider internet world, I don't think people really know or care.

So currently we install and enable a system using an unstandarized protocol 
that works in the same namespace with another protocol that fulfills 
essentially the same purpose and that protocol is at least documented in an 
(Informational) RFC.  The key point here is that the IETF picked one and it 
isn't the one we use.

Personally, I don't like zeroconf a bit.  I like to actually configure my 
boxes before they start to talk to other boxes.  

Additionally, they are both, IMO broken by design.  

Scott K

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