IETF Logo Mail Archive

Re: [ntpwg] Different security mechanisms (NTS, Autokey, Symmetric Security) and key exchange techniques

Hal Murray <hmurray@megapathdsl.net> Tue, 15 March 2016 10:16 UTC

Return-Path: <ntpwg-bounces+ntp-archives-ahfae6za=lists.ietf.org@lists.ntp.org>
X-Original-To: ietfarch-ntp-archives-ahFae6za@ietfa.amsl.com
Delivered-To: ietfarch-ntp-archives-ahFae6za@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 03A6B12D525 for <ietfarch-ntp-archives-ahFae6za@ietfa.amsl.com>; Tue, 15 Mar 2016 03:16:40 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -6.9
X-Spam-Level:
X-Spam-Status: No, score=-6.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.001, RCVD_IN_DNSWL_HI=-5, RP_MATCHES_RCVD=-0.001] autolearn=ham autolearn_force=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 BNKtL75-azcj for <ietfarch-ntp-archives-ahFae6za@ietfa.amsl.com>; Tue, 15 Mar 2016 03:16:38 -0700 (PDT)
Received: from lists.ntp.org (lists.ntp.org [IPv6:2001:4f8:fff7:1::7]) by ietfa.amsl.com (Postfix) with ESMTP id F230312D51A for <ntp-archives-ahFae6za@lists.ietf.org>; Tue, 15 Mar 2016 03:16:37 -0700 (PDT)
Received: from lists.ntp.org (lists.ntp.org [149.20.68.7]) by lists.ntp.org (Postfix) with ESMTP id E08DE86DBF0 for <ntp-archives-ahFae6za@lists.ietf.org>; Tue, 15 Mar 2016 10:16:37 +0000 (UTC)
X-Original-To: ntpwg@lists.ntp.org
Delivered-To: ntpwg@lists.ntp.org
Received: from mail1.ntp.org (mail1.ntp.org [IPv6:2001:4f8:fff7:1::5]) by lists.ntp.org (Postfix) with ESMTP id 74A7786DBBE for <ntpwg@lists.ntp.org>; Tue, 15 Mar 2016 10:16:01 +0000 (UTC)
Received: from mail146c25.carrierzone.com ([64.29.147.216] helo=mail239c25-2586.carrierzone.com) by mail1.ntp.org with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77 (FreeBSD)) (envelope-from <hmurray@megapathdsl.net>) id 1afm12-000Mmw-FS; Tue, 15 Mar 2016 10:16:01 +0000
X-POP-User: hmurray@megapathdsl.net
Received: from ip-64-139-1-69.sjc.megapath.net (ip-64-139-1-69.sjc.megapath.net [64.139.1.69]) by mail239c25-2586.carrierzone.com (8.14.9/8.13.1) with ESMTP id u2FAFmH8000645; Tue, 15 Mar 2016 10:15:49 +0000
Received: from shuksan (localhost [127.0.0.1]) by ip-64-139-1-69.sjc.megapath.net (Postfix) with ESMTP id A1F6B406061; Tue, 15 Mar 2016 00:47:49 -0700 (PDT)
X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.3
To: Harlan Stenn <stenn@ntp.org>
From: Hal Murray <hmurray@megapathdsl.net>
In-Reply-To: Message from Harlan Stenn <stenn@ntp.org> of "Tue, 15 Mar 2016 00:47:12 -0000." <E1afd8i-000PUU-Lu@stenn.ntp.org>
Mime-Version: 1.0
Date: Tue, 15 Mar 2016 00:47:49 -0700
Message-Id: <20160315074749.A1F6B406061@ip-64-139-1-69.sjc.megapath.net>
X-CSC: 0
X-CHA: v=2.1 cv=CYcxutbl c=1 sm=1 tr=0 a=OWgXOY7Tc8w5m7k7nGX6Zw==:117 a=OWgXOY7Tc8w5m7k7nGX6Zw==:17 a=L9H7d07YOLsA:10 a=9cW_t1CCXrUA:10 a=s5jvgZ67dGcA:10 a=kj9zAlcOel0A:10 a=7OsogOcEt9IA:10 a=85N1-lAfAAAA:8 a=dMOfeVZ5Pk92_cRUO74A:9 a=CjuIK1q_8ugA:10
X-CTCH-RefID: str=0001.0A010203.56E7E0D6.004B, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0
X-CTCH-VOD: Unknown
X-CTCH-Spam: Unknown
X-CTCH-Score: 0.000
X-CTCH-Rules:
X-CTCH-Flags: 0
X-CTCH-ScoreCust: 0.000
X-SA-Exim-Connect-IP: 64.29.147.216
X-SA-Exim-Rcpt-To: stenn@ntp.org, ntpwg@lists.ntp.org
X-SA-Exim-Mail-From: hmurray@megapathdsl.net
X-SA-Exim-Version: 4.2
X-SA-Exim-Scanned: Yes (on mail1.ntp.org)
Subject: Re: [ntpwg] Different security mechanisms (NTS, Autokey, Symmetric Security) and key exchange techniques
X-BeenThere: ntpwg@lists.ntp.org
X-Mailman-Version: 2.1.20
Precedence: list
List-Id: IETF Working Group for Network Time Protocol <ntpwg.lists.ntp.org>
List-Unsubscribe: <http://lists.ntp.org/options/ntpwg>, <mailto:ntpwg-request@lists.ntp.org?subject=unsubscribe>
List-Archive: <http://lists.ntp.org/pipermail/ntpwg/>
List-Post: <mailto:ntpwg@lists.ntp.org>
List-Help: <mailto:ntpwg-request@lists.ntp.org?subject=help>
List-Subscribe: <http://lists.ntp.org/listinfo/ntpwg>, <mailto:ntpwg-request@lists.ntp.org?subject=subscribe>
Cc: ntpwg@lists.ntp.org, hmurray@megapathdsl.net
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Errors-To: ntpwg-bounces+ntp-archives-ahfae6za=lists.ietf.org@lists.ntp.org
Sender: ntpwg <ntpwg-bounces+ntp-archives-ahfae6za=lists.ietf.org@lists.ntp.org>

stenn@ntp.org said:
> Specifically, how much time is spent processing each of the first 6 packets?
>  I'm curious how many of these steps are expected to take 1.75 seconds or
> longer. 

Where did the magic number of 1.75 come from?

There is a big difference between "expected" for the normal case and 
something like "happens often enough" so we shouldn't rule it out.

Are you asking about CPU time for client or server to process a packet or are 
you including network transit time?  In either case, it's not hard to come up 
with nasty cases that take a long time.

Bufferbloat can easily get over 2 seconds.  My DSL line is close to 4.

I leave it to your imagination as to how a CPU can take that long.  My straw 
man would be a busy system without enough memory so it's swapping.  Logging 
to a stuck NFS server is another good choice.


-- 
These are my opinions.  I hate spam.



_______________________________________________
ntpwg mailing list
ntpwg@lists.ntp.org
http://lists.ntp.org/listinfo/ntpwg

v2.23.0 | Report a Bug | By Email