IETF Logo Mail Archive

Re: [mdnsext] mdnsext & SLP

Michael Sweet <msweet@apple.com> Fri, 21 June 2013 16:43 UTC

Return-Path: <msweet@apple.com>
X-Original-To: mdnsext@ietfa.amsl.com
Delivered-To: mdnsext@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id ACBFB21F9E97 for <mdnsext@ietfa.amsl.com>; Fri, 21 Jun 2013 09:43:58 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -8.312
X-Spam-Level:
X-Spam-Status: No, score=-8.312 tagged_above=-999 required=5 tests=[AWL=2.286, BAYES_00=-2.599, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_HI=-8]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2yzQciuKhIF4 for <mdnsext@ietfa.amsl.com>; Fri, 21 Jun 2013 09:43:52 -0700 (PDT)
Received: from mail-out.apple.com (mail-out.apple.com [17.151.62.50]) by ietfa.amsl.com (Postfix) with ESMTP id B2E6F21F9EB2 for <mdnsext@ietf.org>; Fri, 21 Jun 2013 09:43:48 -0700 (PDT)
MIME-version: 1.0
Content-type: multipart/alternative; boundary="Boundary_(ID_pnMlK6470zeJgThr0dYd1Q)"
Received: from relay4.apple.com ([17.128.113.87]) by mail-out.apple.com (Oracle Communications Messaging Server 7u4-23.01 (7.0.4.23.0) 64bit (built Aug 10 2011)) with ESMTP id <0MOR001PY53YU6I1@mail-out.apple.com> for mdnsext@ietf.org; Fri, 21 Jun 2013 09:43:38 -0700 (PDT)
X-AuditID: 11807157-b7f706d0000006c6-a4-51c482b72031
Received: from [17.153.35.213] (Unknown_Domain [17.153.35.213]) (using TLS with cipher AES128-SHA (128/128 bits)) (Client did not present a certificate) by relay4.apple.com (Apple SCV relay) with SMTP id 37.83.01734.8B284C15; Fri, 21 Jun 2013 09:43:37 -0700 (PDT)
From: Michael Sweet <msweet@apple.com>
In-reply-to: <CABbPf3hCy0pZ4fatYjab9jCxbayXz0-fUNYbzju3T0mNm-LS+A@mail.gmail.com>
Date: Fri, 21 Jun 2013 12:43:34 -0400
Message-id: <4A8CEE77-B266-45E7-9D46-1ABB07C82CF0@apple.com>
References: <CABbPf3gpc_BFK5aFHVQHRwKnYwXVGXnFQKrvHbj-=_b_KbAxQQ@mail.gmail.com> <BCBFAA10-634B-4479-A653-25655236801E@apple.com> <CABbPf3hCy0pZ4fatYjab9jCxbayXz0-fUNYbzju3T0mNm-LS+A@mail.gmail.com>
To: Garret Peirce <peirce@maine.edu>
X-Mailer: Apple Mail (2.1764)
X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrCLMWRmVeSWpSXmKPExsUiOFP5qu7OpiOBBlsv6lmcXHKKyeLIt1iL XQcmMDowe2w9+YPNY8mSn0wep3+1MgcwR3HZpKTmZJalFunbJXBlPD67jrXgjWrF5RtHGRsY Xyh0MXJySAiYSEw/94AVwhaTuHBvPVsXIxeHkEAvk8S1xitgCWEBFYl9czewg9i8AnoS2xYe ALOZBRIkGqYdYgOx2QTUJH5P6gOr5xQIlPhw5hsLiM0ioCpxef0tJoh6ZYkV024wQcyxkTh2 6BozxLJjjBKb5ywBaubgEAFatuNgIcRBshIT+64xTmDkm4Vk9SwkqyFsbYllC18zQ9h6Ei+b 3rFjiutKXFw3iXEBI9sqRoGi1JzEShO9xIKCnFS95PzcTYygsG0oDN/B+G+Z1SFGAQ5GJR7e A6lHAoVYE8uKK3MPMUpwMCuJ8LIHAYV4UxIrq1KL8uOLSnNSiw8xSnOwKInzbnx1MFBIID2x JDU7NbUgtQgmy8TBKdXA2J3SZ63pZuVQ/6Lu+rbl95ac5/sTxXQstn/tN9uTP1h4+IUTnBRv Svft/bpE68yZn//DexP/5JXN8blsO32C1LqPQJYii2Bxqfy6PXfO746qEO5nTD3zUytpyq7r pbrLW89WbN8cpyWTvafZWlTYW1NoytyF7tOb1xzIlxdM3C+832ZZc68SS3FGoqEWc1FxIgB9 vjyvVwIAAA==
Cc: IETF mdnsext <mdnsext@ietf.org>
Subject: Re: [mdnsext] mdnsext & SLP
X-BeenThere: mdnsext@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: "Discussion of extensions to Bonjour \(mDNS and DNS-SD\) for routed networks." <mdnsext.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mdnsext>, <mailto:mdnsext-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/mdnsext>
List-Post: <mailto:mdnsext@ietf.org>
List-Help: <mailto:mdnsext-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mdnsext>, <mailto:mdnsext-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 21 Jun 2013 16:43:58 -0000

Garret,

On Jun 21, 2013, at 12:15 PM, Garret Peirce <peirce@maine.edu> 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:

    service:printer:ipp://192.168.0.100/ipp/print
    service:printer:ipp://10.0.1.100/ipp/print
    service:printer:ipp://[fe80::0100]/ipp/print
    service:printer:ipp://hostname.local./ipp/print
    service:printer:ipp://17.1.2.100/ipp/print
    service:printer:ipp://hostname.apple.com/ipp/print

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

_________________________________________________________
Michael Sweet, Senior Printing System Engineer, PWG Chair

v2.23.0 | Report a Bug | By Email