From nobody Tue Nov 17 06:26:39 2020 Return-Path: X-Original-To: teas@ietfa.amsl.com Delivered-To: teas@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id AFFB23A1383; Tue, 17 Nov 2020 06:26:37 -0800 (PST) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -1.098 X-Spam-Level: X-Spam-Status: No, score=-1.098 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, FREEMAIL_REPLY=1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=no autolearn_force=no Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com 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 pmryCQ5OlBaA; Tue, 17 Nov 2020 06:26:36 -0800 (PST) Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E53DF3A138F; Tue, 17 Nov 2020 06:26:11 -0800 (PST) Received: by mail-wr1-x432.google.com with SMTP id 23so23340320wrc.8; Tue, 17 Nov 2020 06:26:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=TmZ3m+QF5Gob803ZMz59v+sS0EGABiG2mBAS05jK3pA=; b=pHttUw1pmh+NO7TjWwLRY/IV7YUC0G+FRyiaCqxTDbPv7Oueshhg5edVaqy3ylV/F0 36xMs63QXkkTsvmKxyTGuirjkNcxX8S8ojE3FPpoaXU/kU8QPorKl1p1yGdNW+IGIwFi kzvvhb/dh1cAeUyGUkxteNGp6ay8/NZ3tGPxFFzu+/9KUcppBxrIexLAVUl5sU6TJ9gA A6oaDpfUyuXWIscXnRpnKr5pgQlKv9vgBblIa75aQGyq8CrZAtRRdYBRgwDoH+uLeuPd 2vDg6+QffSlXAmo/5D3L8rNWPRrTXGIRXhcz64zSnut7p78yfIhC1aG4/Q/sC/AVvMFt A2cA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=TmZ3m+QF5Gob803ZMz59v+sS0EGABiG2mBAS05jK3pA=; b=FsBXRDu8CW/F4eOpSVvtzunrc9nmwcaWc9UCbcZ1RF90Ag20bRC/hBa8oVeqhW83HH TDOEXz2s/5hgTSbxAfxxTpQI9xBBz4cV2XzJb00DKCVnVFrKqmjjv2aQZZt37EZcCBXU zWXNE3NgIFerqO6I1MNYWCGPNyHQRd8ZQCGztl6dj93BkDtg0AaBrxSXfgfbUo6G6457 Or8r9Y4fCEmndyCyraD0PmsMqi9vlfjmG/nOSLAv1ufSP3Q7Hr7aaKIUdaF5ymDr/6mf 99ZlGUdRM6pwEeEjP0vcp/iDHlpz/Wq46YQ4LDY0bD5+kiqUHvbON7WRJ7XSZLqpj5z4 ZcEg== X-Gm-Message-State: AOAM533o9I+/pOWWAKcXPTVUgABMAur0bz7ldr7F0hhfYt/9yZFuq1Ik 2KUewISKoNH88CPlr+FZyes= X-Google-Smtp-Source: ABdhPJxiD2w8hq54oyCgcQDqFu6S/oARml4lGeT+/dQftf1XPUpy/tmzXLE65k50HdiMc8StD0BK0Q== X-Received: by 2002:a5d:634b:: with SMTP id b11mr24593731wrw.97.1605623170296; Tue, 17 Nov 2020 06:26:10 -0800 (PST) Received: from broadband.bt.com ([2a00:23c5:3395:c901:15b6:918e:5493:f277]) by smtp.gmail.com with ESMTPSA id d63sm3892147wmd.12.2020.11.17.06.26.09 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 17 Nov 2020 06:26:09 -0800 (PST) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.4\)) From: Stewart Bryant In-Reply-To: <62c75774-4032-854f-f03b-4d5127819a68@joelhalpern.com> Date: Tue, 17 Nov 2020 14:26:08 +0000 Cc: Stewart Bryant , teas@ietf.org, draft-nsdt-teas-ietf-network-slice-definition@ietf.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <059e01d6b6ce$0f74a830$2e5df890$@olddog.co.uk> <9e8170c6-399b-e954-2abb-5e5f425f172a@joelhalpern.com> <13178999-9168-46fb-8455-36d4d5683a2e@Spark> <62c127a5-9230-d105-04b7-4b061fdd43c1@joelhalpern.com> <879FFB4D-3E9B-498C-BF40-B30252A8F273@gmail.com> <4ACEF52F-BF99-4B45-BFA0-B0C221E4D4E7@gmail.com> <62c75774-4032-854f-f03b-4d5127819a68@joelhalpern.com> To: Joel Halpern X-Mailer: Apple Mail (2.3608.120.23.2.4) Archived-At: Subject: Re: [Teas] Thoughts about draft-nsdt-teas-ietf-network-slice-definition and isolation X-BeenThere: teas@ietf.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Traffic Engineering Architecture and Signaling working group discussion list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Nov 2020 14:26:38 -0000 > On 17 Nov 2020, at 10:28, Joel M. Halpern wrote: >=20 > Is this analogous to specifying a burst rate with several rates over = several time periods (only we are talking about operator ccommitments = rather than customer commitments)? >=20 > If so, might this be something like a multi-level delay bound = commitment, e.g. > For a given pair of ports > 99% of your traffic will get there in 10 ms, and > 90% of your traffic will get there in 100 ms Yes, but they do it as a rolling average, so sample every 1ms (say) = sample 1..10 gives 10ms, sample 2..11 give 10ms result2, then 1..100 = gives 100ms result1, 2=E2=80=A6100 gives 100ms result2. Now there is a cool thing in the timing world, but the slope of the = curve at a point in the curve tells you the cause of the error. I am not = sure if this would apply to our application, but it is worth thinking = about. > (I know, sloppy example, just trying to see if I am understanding the = idea.) >=20 > If that is the idea, I am missing the aspect of "from outside". =46rom = the customers perspective all problems are "from outside". Whether that = outside is a backhoe or competing traffic. I suppose you are right, but in this world it does not have to be = congestion, there may be enough macro bandwidth, just not at the right = ns which is on a much finer granularity than we are used to, and is more = transient than we are used to. - Stewart >=20 > Yours, > Joel >=20 > On 11/17/2020 5:22 AM, Stewart Bryant wrote: >> They are terms from the timing world where you look at a defect in = terms of its probability within a window within a larger observation = period. >> = http://www.chronos.co.uk/files/pdfs/itsf/2008/Day2/Packet_TDEV_MTIE_and_MA= TIE_for_Estimating_the_Frequency_and_Phase_Stability_of_a_Packet_Slave_Clo= ck_(Antti_Pietilainen,_NSN).pdf = >> ITU define MTIE in G.810, but they are looking at a different class = of application (frequency transfer), but I think the concept translates = over here. >> If you look at slide 5 =E2=80=9CMTIE of a practical packet clock=E2=80=9D= you get the idea, but I think it needs expanding and applying to other = characteristics. >> Now some of the error sources will be within the slice, but we also = need to worry about error sources induced from outside the slice. >> Best regards >> Stewart >>> On 17 Nov 2020, at 10:05, Joel Halpern Direct = > wrote: >>>=20 >>> Stewart, I think you are raising an interesting question, but one = where I got lost part way through. >>>=20 >>> Can you elaborate one what you mean by "something analogous to MTIE = and TDEV to describe packet and network interaction". >>>=20 >>> Thank you, >>> Joel >>>=20 >>> On 11/17/2020 4:57 AM, Stewart Bryant wrote: >>>>> On 9 Nov 2020, at 23:37, Jeff Tantsura >> wrote: >>>>>=20 >>>>> I don=E2=80=99t think mixing performance objectives with isolation = is a great idea though, >>>>> an SLA doesn=E2=80=99t change because there=E2=80=99s someone else = sharing infrastructure with you, it is well understood that any changes = within other customers should not affect you. >>>> No, but in this class of networks the interaction between customers = may be a lot more sensitive and detailed than we are used to. For = example the single metrics that we normally associate with delay and = jitter will likely become a mask in the same way that time and frequency = transfer system find necessary to completely specify and instrument the = behaviour of the subs system. We will likely need something analogous to = MTIE and TDEV to describe packet and network interaction. >>>> I therefore think it is useful to have an umbrella term for concept = and the set of metrics that are of necessity more complex and critical = than we are used to. >>>> A possible alternative umbrella term is network cross talk. We = understand the concept of crosstalk at the physical layer. The concept = here in terms of performance is that packets do not interact at the = micro level as well as the more normal macro level. >>>> However, isolation has other feature that we need to think about = under this umbrella, for example the need to only mix certain types of = traffic allow (or exclude) traffic to flow over certain geographies or = through nodes manufactured by certain countries. We do not have to agree = with these constraints, but we need to accept that they are becoming a = reality. >>>> Now we could achieve the above by buying dedicated fibre or = dedicated hardware, but that that does not support economies of scale. >>>> I would be fine with us using a term other than isolation, but I = think it is worthwhile highlighting that we are not in =E2=80=9Cordinary=E2= =80=9D SLA territory with this, but that it is more complex and more = detailed, and a top level term to group these characteristics is in my = view helpful. >>>> Best regards >>>> Stewart