From owner-freebsd-current Fri Mar 17 12:38:57 2000 Delivered-To: freebsd-current@freebsd.org Received: from mail.infolibria.com (mail.infolibria.com [199.103.137.198]) by hub.freebsd.org (Postfix) with ESMTP id 8CED037B815 for ; Fri, 17 Mar 2000 12:38:45 -0800 (PST) (envelope-from loverso@infolibria.com) Received: from infolibria.com (border [199.103.137.193]) by mail.infolibria.com (Postfix) with ESMTP id 00699DDB83; Fri, 17 Mar 2000 15:36:59 -0500 (EST) Message-ID: <38D2985C.F090D9C9@infolibria.com> Date: Fri, 17 Mar 2000 15:41:00 -0500 From: John LoVerso Organization: InfoLibria X-Mailer: Mozilla 4.72 [en] (WinNT; U) X-Accept-Language: en MIME-Version: 1.0 To: Tom Embt , freebsd-current@FreeBSD.ORG Subject: Re: Why not gzip iso images? References: <8aorf2$htp$1@atlantis.rz.tu-clausthal.de> <3.0.3.32.20000317092038.0078a018@mail.embt.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > Had > the file been split and a checksum computed for each piece, I could have > grabbed only the affected portion of the ISO. This is screaming for an FTP server mod similar to the wuftpd code that will automatically run tar|gzip. That is, given a file "foo", serve "foo.aa" to be the first (server-defined) chunk size of the file. Define "foo.md5" to be a (precomputed) list of md5 checksums for each chunk. The ftp server automatically just open's and seeks in the single file and returns the proper amount of bytes. Result: server only stores 1 copy (the whole, large file), the clients can grab either the whole or the parts. For instance, ftp://ftp.freebsd.org/pub/FreeBSD/releases/4.0-RELEASE/bin/bin.tgz might be served with a chunk size of 235Kb. BTW, other than the checksums, it is possible for an ftp client to grab arbitrarily sized chunks of a file using the FTP "RESTart" option. I don't know of a client that supports this, but it would be easy to add. John To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message