From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:57289) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S5xvF-0000Sk-OZ for qemu-devel@nongnu.org; Fri, 09 Mar 2012 06:23:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1S5xuk-0001gh-6p for qemu-devel@nongnu.org; Fri, 09 Mar 2012 06:23:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:2321) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S5xuj-0001gS-VP for qemu-devel@nongnu.org; Fri, 09 Mar 2012 06:23:14 -0500 Message-ID: <4F59E8F2.2060106@redhat.com> Date: Fri, 09 Mar 2012 12:26:42 +0100 From: Kevin Wolf MIME-Version: 1.0 References: <4F4E9E31.50903@storagecraft.com> <4F4F8FCD.7010106@redhat.com> <4F4FD1C9.8050006@storagecraft.com> <4F58CD9A.3000708@redhat.com> <3580B6302539E34585A612F5932C1F2F01A0D97F@STC-EXCH.stc.local> <4F59CBFC.7040906@redhat.com> <4F59DB5A.1020809@redhat.com> In-Reply-To: <4F59DB5A.1020809@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Add support for new image type List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Nate Bushman , Kai Meyer , "qemu-devel@nongnu.org" Am 09.03.2012 11:28, schrieb Paolo Bonzini: > Il 09/03/2012 10:23, Kevin Wolf ha scritto: >>> You make really good points on opening up the image file format. >>> I see real value there in that it would foster development of >>> other solutions around that format. The problem in this case is >>> that StorageCraft's backup image format uses proprietary >>> compression and encryption, and so, regrettably, we can't >>> (currently) open up that code. >> >> This is an interesting statement. Not so much for compression, for >> which I can't know how much better your solution is than common >> algorithms. But I always thought that closed encryption algorithms >> have to be considered bad, because using them would mean relying on >> security by obscurity. Which probably everyone agrees is a bad idea. > > And even for compression, having an open decompressor is usually a good > idea. Some people have no problems with proprietary solutions but do > not like lock in (and wonder what to do with their backups if > StorageCraft disappears). The lock-in you already get with uncompressed images, but yes, it's a problem with this file format that would make me avoid it. Kevin