Return-Path: X-Original-To: cfrg@ietfa.amsl.com Delivered-To: cfrg@ietfa.amsl.com Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B18A01A6FC1 for ; Tue, 12 Aug 2014 18:49:06 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -1.379 X-Spam-Level: X-Spam-Status: No, score=-1.379 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FM_FORGED_GMAIL=0.622, SPF_PASS=-0.001] autolearn=no 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 zmejgheWsrOm for ; Tue, 12 Aug 2014 18:49:05 -0700 (PDT) Received: from mail-pa0-x231.google.com (mail-pa0-x231.google.com [IPv6:2607:f8b0:400e:c03::231]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 8BC7C1A6FBC for ; Tue, 12 Aug 2014 18:49:05 -0700 (PDT) Received: by mail-pa0-f49.google.com with SMTP id hz1so13968514pad.36 for ; Tue, 12 Aug 2014 18:49:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=securityinnovation.com; s=google; h=from:references:in-reply-to:thread-index:mime-version:date :message-id:subject:to:cc:content-type; bh=TJktRUpi2r0S1FoIq8izq4VqHJm7pDpORROeKz3mqwU=; b=K9rMehbsQoBUOPYOy0DePljUpbOmQzE4ilSbJZulpFE5ZpoGC43IYCnsEO/yRcMCUm TBn+moG+viBRs5cSrbePHDRnb6LZH8N17REgyATsXEaDPr5cocPuv9QqLU/ofcOczbaa doyb/HrujcEqfjdYG9KlCvS58mt2B7K6/30Ss= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:references:in-reply-to:thread-index :mime-version:date:message-id:subject:to:cc:content-type; bh=TJktRUpi2r0S1FoIq8izq4VqHJm7pDpORROeKz3mqwU=; b=NAyZWskKz+EbTP+7E9BcKWCqgQhHsDHzBPK8N1zHVE7FSTw5ttZUOlA64YULb/Ncl0 Oq7b1/nILXAuJzCl/rvmQBlqfj7UCIdJzkUyLpL92gARpC3y++LE6RtPgU1H0xXkuucu 8y7P4gZHfUItRMRYh1NY99A2JPx0dNAiKJwcZEm+LbxGNhjbvHYYkNuLDd9NoG0BoAkp CmbNJAz3QfJaaX5b49Br21Qr8Es3WokEDFqAKUV6leUa16UqW9yIbgNw5lq8id69siY9 hxPWwibJ5Pu+k9YJ/JiwKM/D2LN7UJk65bj+OTh+bhlsddUOVvT6D1pS7Fdpnf0ySULD QMdw== X-Gm-Message-State: ALoCoQnOy6JxGr4r9dPyqzqANXDKTR65HxBsw3AjCRYgI7PKVrneLdmxuJQQHf0OpmCK8kiR3Chq X-Received: by 10.66.220.230 with SMTP id pz6mr51075pac.145.1407894545046; Tue, 12 Aug 2014 18:49:05 -0700 (PDT) From: William Whyte References: In-Reply-To: X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQIhVhc0dkfrh7tpttcVSPrwLyg8AwGOsYN+mx4OgFA= MIME-Version: 1.0 Date: Tue, 12 Aug 2014 21:49:03 -0400 Message-ID: <18ebdc0905191cd01ae23058180370b2@mail.gmail.com> To: Watson Ladd , Benjamin Black Content-Type: multipart/mixed; boundary=047d7b5d9a2b3e8135050078fed5 Archived-At: http://mailarchive.ietf.org/arch/msg/cfrg/S8BNwyaJXNQQSQx6EVna4wB93hY Cc: cfrg@ietf.org Subject: Re: [Cfrg] Requirements for curve candidate evaluation update X-BeenThere: cfrg@irtf.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Crypto Forum Research Group List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Aug 2014 01:49:06 -0000 --047d7b5d9a2b3e8135050078fed5 Content-Type: text/plain; charset=UTF-8 [Benjamin Black] > 5. No changes to coordinate wire formats. [Watson Ladd] > Does this mean just Weierstrass? Or is a change to Edwards somehow not a change in the wire format? (Of course this doesn't constrain the curves either) Requirement 5 strikes me as entirely unnecessary. Why is it important that two different curves have the same wire format? The wire format can be one of the things identified by the curve identifier, and each curve will have a certain amount of custom code anyway; why does it matter if this custom code includes code to interpret the wire format? I'd like to see this requirement more thoroughly justified. 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