From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E54DAC3A5A2 for ; Tue, 3 Sep 2019 16:17:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3AEA2341F for ; Tue, 3 Sep 2019 16:17:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Oi5pIQeU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730036AbfICQRN (ORCPT ); Tue, 3 Sep 2019 12:17:13 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:39537 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728571AbfICQRN (ORCPT ); Tue, 3 Sep 2019 12:17:13 -0400 Received: by mail-wr1-f67.google.com with SMTP id t16so18163458wra.6 for ; Tue, 03 Sep 2019 09:17:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=e1amEEi7DPleRDG4iwwlMlME+rEqQsHQWVcEf1HZJDk=; b=Oi5pIQeUGiG/BPcOqP3Lv4SwTaWI0ADcoHLhXf/vQK76+p+/deVdjuSPrIgIg7oTOm IBmk7o0+9wVdoPfL/YcX7ldQ347HyAyG6oRoh1ePoRCzo1nmGF5DEWa0VtuXLoDweQi9 +wCKx7eFX22DQtydqIsQ4jQ1wq5RXa734QWQuNmMsMO/5S6CyA5sNjQemTyxmJZE8OUy Qj8ZjHQMjCD67VgLShJ2ZeBaEvurK2/Z7FFR2NDKcBMJy3NpONNkcaxGqNm6r38FwQ2Y 6ol4XdlHF5XsfWPf/nzcKNEG2+R0jMRcF46Fhn4DRQsSsa3JfBW/OmPT61XcFZPCRDdn ruAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=e1amEEi7DPleRDG4iwwlMlME+rEqQsHQWVcEf1HZJDk=; b=OYINvCTLCFjIAvW34p8GciBdr5GGFi4Mu0oi47w4oibsWvJxyE9e7QxCG0LMnDwxW0 aXkxln+sw3p1/5q4JrcYWGtAti86FRlN0sjsF0wtXruVZ2rk7zWj+mLNaempye1l+QX3 Oy80bKbsHb+SPt3aHJTWzW4mar/oOU1AJ+lH4jZcK1tts5Iaus4keqwrjKwDFvnBKFaK KYlWxFUU+0VIGlGtY0BO3m3a1yGY9TZgu4I4YnX6hKIt6I2V7ztNPh4DHHAt/N66lHtR lz17AbG1q/uTymIQ3ZRqA40YdzuYorRWx8UjnbMEIj/cgobNkBUwMkY0bTkilgLAbaRt vveg== X-Gm-Message-State: APjAAAXFnt8q6QgBOeIg7ITNbZCe3MriL+BP+RCdJCG4OggV09rMt2I+ 1xvm5X34kUZVcwVxQ3mrvEw= X-Google-Smtp-Source: APXvYqz3d/ClUWRkLtdLQNijnlJ4gfrZjRtkVEEKE6TnUHYwaMBEFgRlLQCnxdBcu7Oz+6XHY7MDUg== X-Received: by 2002:a5d:6ac8:: with SMTP id u8mr7959317wrw.104.1567527431480; Tue, 03 Sep 2019 09:17:11 -0700 (PDT) Received: from [192.168.8.147] (83.173.185.81.rev.sfr.net. [81.185.173.83]) by smtp.gmail.com with ESMTPSA id j20sm27829937wre.65.2019.09.03.09.17.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 03 Sep 2019 09:17:11 -0700 (PDT) Subject: Re: [PATCH] Clock-independent TCP ISN generation To: Cyrus Sh , Eric Dumazet , davem@davemloft.net Cc: shiraz.saleem@intel.com, jgg@ziepe.ca, arnd@arndb.de, netdev@vger.kernel.org, sirus@cs.utah.edu References: <70c41960-6d14-3943-31ca-75598ad3d2d7@gmail.com> <2cbd5a8f-f120-a7df-83a3-923f33ca0a10@gmail.com> From: Eric Dumazet Message-ID: <492bb69e-0722-f6fc-077a-2348edf081d8@gmail.com> Date: Tue, 3 Sep 2019 18:17:09 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 9/3/19 6:06 PM, Cyrus Sh wrote: > > > On 9/3/19 9:59 AM, Eric Dumazet wrote: >> >> You could add a random delay to all SYN packets, if you believe your host has clock skews. > > In theory yes, but again do you know any practical example with tested > applications and the list of the rules? I'm interested to see an actual example > that somebody has carried out and observed its results. > Do you have a real program showing us how this clock skew can be used practically ?