[DNSOP] SVCB without A/AAAA records at the service name

Martin Thomson <mt@lowentropy.net> Thu, 14 January 2021 23:43 UTC

Return-Path: <mt@lowentropy.net>
X-Original-To: dnsop@ietfa.amsl.com
Delivered-To: dnsop@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id A28E43A09C3 for <dnsop@ietfa.amsl.com>; Thu, 14 Jan 2021 15:43:40 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.101
X-Spam-Level:
X-Spam-Status: No, score=-2.101 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=lowentropy.net header.b=SrzAlJGa; dkim=pass (2048-bit key) header.d=messagingengine.com header.b=L8Zw49Qd
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id o3p_zxeZnS3m for <dnsop@ietfa.amsl.com>; Thu, 14 Jan 2021 15:43:39 -0800 (PST)
Received: from wout5-smtp.messagingengine.com (wout5-smtp.messagingengine.com [64.147.123.21]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 57C6C3A09BB for <dnsop@ietf.org>; Thu, 14 Jan 2021 15:43:39 -0800 (PST)
Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.west.internal (Postfix) with ESMTP id 3E721A17 for <dnsop@ietf.org>; Thu, 14 Jan 2021 18:43:38 -0500 (EST)
Received: from imap10 ([10.202.2.60]) by compute1.internal (MEProxy); Thu, 14 Jan 2021 18:43:38 -0500
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lowentropy.net; h=mime-version:message-id:date:from:to:subject:content-type; s= fm1; bh=exg3F+v4nYQjuMfdIcXr/91McIax/Esj4j6Sv6/M2ns=; b=SrzAlJGa QNEBZTIDUjx4XXxRHiWHbFFHQBCGCnjsa+zSjpV7C9NUonrcBjOfeg2+TMiifMIG VYblJGqMAcYbj60LvVNj+Wzh/FV6CKwy9lcufLcx917hKcQYmZGMywOmG9Rmve/x Y3EBkCmo+w8EA449UtCg0T81LHZpgw7q0s2Pz/2L3pYfb/brYlk+9b0WVZ/ElI5e fW3+/1hST2yADJYHuhijEgJqIV7XUacLJYX6ysVv/OWlYbsMXqNaUa/ySpglLcdZ Lkcu2qBNHfHkq0PhOrem1EjeceWZVZ9YUyfGY/u8Gy1IZV4VPfTYPU9np/A6oxPx 0YpvSZ4mbeYahA==
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:date:from:message-id :mime-version:subject:to:x-me-proxy:x-me-proxy:x-me-sender :x-me-sender:x-sasl-enc; s=fm1; bh=exg3F+v4nYQjuMfdIcXr/91McIax/ Esj4j6Sv6/M2ns=; b=L8Zw49QdIv5iM12joFfDgteuQfiwcgED3n64dMI7C+lvS HOz2stbxWutsIBOQkkbl0I2raYeq66J8W+53EuJLVsXM/Mw1xAAZ/1LBxQ1etsKQ Xxm5nNX0rVWSOeWKTQudK/mX271eN/26MWLxLrhip1kykDo02+UERjSTtx/jSKyB rd+PXp3WRs9TbDcbH4trBHmnJkCAEcYH0SPzPg5g3FAbsl4dyjyNKC9fD7NlCT8B CcF3/HOILfNCHCSAd1RPLQw0T2H7ifc5RlEwLxXecNW76oyAP7qRpqWFQlBn6hr2 DeXbQCao1oECnsWgNZBt2byXG/eP5IzIegriSqBrg==
X-ME-Sender: <xms:KdcAYE7OoKaBM8kuaT08AD5NAW-KrWg2bhgT8wjvEXK_YdTTSlwoDw> <xme:KdcAYF4HsIdYS_KO6alHFK4h8IslGqOm3gDhkUq5PqQ9V1iYEtreZMTcRvN1R6Aas wdgUrW4i5XT4S2mxdg>
X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledrtddugddufecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhepofgfggfkfffhvffutgesthdtredtre ertdenucfhrhhomhepfdforghrthhinhcuvfhhohhmshhonhdfuceomhhtsehlohifvghn thhrohhphidrnhgvtheqnecuggftrfgrthhtvghrnhepgeeuheeujedvieevffehvdekge ffkefggfdtteelfeekfeeftdejhfdtuddvuddtnecuffhomhgrihhnpehgihhthhhusgdr tghomhenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpe hmtheslhhofigvnhhtrhhophihrdhnvght
X-ME-Proxy: <xmx:KdcAYDfvmTLX1HToRc3-YODvO-AEmlJY8tAXu2xRqDkmh0kO-0m5nw> <xmx:KdcAYJKwDVbi5nvr4I8G9_MvTWY3yGb89WQ5ddgiIEmnnZMuK1SScg> <xmx:KdcAYIIeU498CVw72jaLCCVSc_BnLErr6_5SwdhcyXgLHkQnftjSVA> <xmx:KdcAYNV0cyqKwjlv41U7ojNGMm5bR3Zj3a69Z-nCBdnvmt5PWX0spw>
Received: by mailuser.nyi.internal (Postfix, from userid 501) id A1A2020256; Thu, 14 Jan 2021 18:43:37 -0500 (EST)
X-Mailer: MessagingEngine.com Webmail Interface
User-Agent: Cyrus-JMAP/3.5.0-alpha0-45-g4839256-fm-20210104.001-g48392560
Mime-Version: 1.0
Message-Id: <2e1054a0-5a7a-4d62-92a1-095217af82bb@www.fastmail.com>
Date: Fri, 15 Jan 2021 10:43:17 +1100
From: "Martin Thomson" <mt@lowentropy.net>
To: dnsop@ietf.org
Content-Type: text/plain
Archived-At: <https://mailarchive.ietf.org/arch/msg/dnsop/9UkeCnVoxxz4Iql_x9TESfRsJ34>
Subject: [DNSOP] SVCB without A/AAAA records at the service name
X-BeenThere: dnsop@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: IETF DNSOP WG mailing list <dnsop.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/dnsop>, <mailto:dnsop-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/dnsop/>
List-Post: <mailto:dnsop@ietf.org>
List-Help: <mailto:dnsop-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/dnsop>, <mailto:dnsop-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 14 Jan 2021 23:43:41 -0000

As requested (I'm not engaged here enough to understand the terms of engagement, so my apologies for using an interaction form I'm accustomed to), moving discussion from https://github.com/MikeBishop/dns-alt-svc/issues/287 to here:

The SVCB draft basically mandates a fallback to A/AAAA.  I think that this is not universal and that this should instead be made an option.

For HTTP, the fallback is necessary.  For a new protocol, a fallback could be undesirable.  Especially if you want to deploy that protocol using a service name on which you have already deployed HTTP.  If you don't want your HTTP servers getting connection attempts for the new protocol, the fallback is more nuisance than useful.