Re: [spring] [bess] [Pals] [EXTERNAL] Re: Martini Pseudowires and SR

Ketan Talaulikar <ketant.ietf@gmail.com> Tue, 31 May 2022 16:52 UTC

Return-Path: <ketant.ietf@gmail.com>
X-Original-To: spring@ietfa.amsl.com
Delivered-To: spring@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 1E3E2C157B49; Tue, 31 May 2022 09:52:38 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.107
X-Spam-Level:
X-Spam-Status: No, score=-2.107 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, HTML_MESSAGE=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_BLOCKED=0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5EzIQp-HkX3E; Tue, 31 May 2022 09:52:34 -0700 (PDT)
Received: from mail-vk1-xa2a.google.com (mail-vk1-xa2a.google.com [IPv6:2607:f8b0:4864:20::a2a]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 2CCFBC157B4B; Tue, 31 May 2022 09:52:34 -0700 (PDT)
Received: by mail-vk1-xa2a.google.com with SMTP id b81so6484560vkf.1; Tue, 31 May 2022 09:52:34 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=9tEUfVF/vPy6vwe5efF0dlX7DyxneElDkalc3pqnX7A=; b=lH+SCwomJO9y874/A9sVtxSQiqb13iS5ddgH/njj/AwnWUaT5bk/nrgSp78jen8Z7z f+ZTZ007WuJeTR0zu4rIrzn64LPGvL0Wk4LSLX1O+ob2UhjaN9uF0Br+k4txbORt9nLk QwtTUTWiITVzMOTlaEcTKHMzpGz+XGcPLSpsckk4a0SJHFmXDb4Oy/gebpsbJjPeEHeS owzg9JatYbmzwUsBsjSyWsanSk0WtsluDzu63jcXBOtLKNFLi0xJIPx891F1OOIpQm8u STRGKw7aJ/PZ/gp2P1ksW27DNqXsq2BTs2BwsZXHBEeOyB1kKcPhrQb2ZL969ialMlfN 1JHA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=9tEUfVF/vPy6vwe5efF0dlX7DyxneElDkalc3pqnX7A=; b=Bf10K5ceLSzh7rlhG8WFc+6+ZqUT5nZcmm9KvtW4GScu6N66I7O2d83w5ODY50T5ne j9l21NJhmeEjy1vfdm0jJ5lXCXvNFZHO3sZTRqC55qXXC18YAIY2PabsnwMKXSaXcekb Agl8uTk1RhDru4C0mrY/jPKAgud5s/DsQRWwSIuLycSpuWOHiMMGOafzM4ugEl8Gbw7U 2VKOZDn98F6xdYnYkD8CuRjWJcKLrGSgfJWig9YxoZbOIOXim6otpSwMDJG5v6uTSJzT IlmjxjJvAVHUm9aWdRg8nu9zuKbF1M4jux9Nxp4qolEsas32cyXM4MWPXMUuC4+hTOxZ yZlg==
X-Gm-Message-State: AOAM530QkQ0Pw9XnPq1/rPZ1c9yzmytq8lR7V3pxYHRXe/sBQRxGl69z YHBtF9k+5VxNOm+mCDniqXLlSgndkRY8j6nsSzY=
X-Google-Smtp-Source: ABdhPJxwqbOGRqWdsRWv+iAKeWRKTF0Hj8ntSmmzrtozVo8Bc1glHffaT/MxZcKK6pMuMABVwu/rlK6HvjhJyJDFgkQ=
X-Received: by 2002:a1f:2a01:0:b0:357:907f:7dea with SMTP id q1-20020a1f2a01000000b00357907f7deamr17820704vkq.7.1654015953047; Tue, 31 May 2022 09:52:33 -0700 (PDT)
MIME-Version: 1.0
References: <AM7PR03MB64514C7EA1750090FE94192CEEDD9@AM7PR03MB6451.eurprd03.prod.outlook.com> <51706C42-15E2-442D-916E-627769062F22@gmail.com> <PH0PR03MB6300D250BC9F3762D91E0337F6DD9@PH0PR03MB6300.namprd03.prod.outlook.com> <BY3PR08MB70600C3B393A3B2E4FCF0671F7DD9@BY3PR08MB7060.namprd08.prod.outlook.com> <PH0PR03MB6300E03FCF3C0307ADC9D71AF6DC9@PH0PR03MB6300.namprd03.prod.outlook.com>
In-Reply-To: <PH0PR03MB6300E03FCF3C0307ADC9D71AF6DC9@PH0PR03MB6300.namprd03.prod.outlook.com>
From: Ketan Talaulikar <ketant.ietf@gmail.com>
Date: Tue, 31 May 2022 22:22:21 +0530
Message-ID: <CAH6gdPz1=_RkWQ0Hekh_jhiLGQP+80dExeJwRg02ScoB-6f1Jg@mail.gmail.com>
To: Alexander Vainshtein <Alexander.Vainshtein@rbbn.com>
Cc: "Rabadan, Jorge (Nokia - US/Sunnyvale)" <jorge.rabadan@nokia.com>, Andrew Alston - IETF <andrew-ietf=40liquid.tech@dmarc.ietf.org>, mpls-chairs <mpls-chairs@ietf.org>, Stewart Bryant <stewart.bryant@gmail.com>, SPRING WG <spring@ietf.org>, "pals@ietf.org" <pals@ietf.org>, "bess@ietf.org" <bess@ietf.org>
Content-Type: multipart/alternative; boundary="0000000000005595c005e05199e6"
Archived-At: <https://mailarchive.ietf.org/arch/msg/spring/CJHVS9ENuuRyKGTMNnsQRhIYU14>
Subject: Re: [spring] [bess] [Pals] [EXTERNAL] Re: Martini Pseudowires and SR
X-BeenThere: spring@ietf.org
X-Mailman-Version: 2.1.34
Precedence: list
List-Id: "Source Packet Routing in NetworkinG \(SPRING\)" <spring.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/spring>, <mailto:spring-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/spring/>
List-Post: <mailto:spring@ietf.org>
List-Help: <mailto:spring-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/spring>, <mailto:spring-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 31 May 2022 16:52:38 -0000

+ 1 to Sasha and Jorge

The feature gaps to be addressed in BGP EVPN VPWS should be based on
operators' feedback so we add only those that are relevant.

Thanks,
Ketan


On Tue, May 31, 2022 at 4:59 PM Alexander Vainshtein <
Alexander.Vainshtein@rbbn.com> wrote:

> Jorge and all,
>
> Here is a (admittedly incomplete) list of things that, AFAIK, today are
> not supported with EVPN VPWS:
>
>    1. All the non-Ethernet PW types (28 such types can be found in the IANA
>    registry
>    <https://www.iana.org/assignments/pwe3-parameters/pwe3-parameters.xhtml#pwe3-parameters-2>
>    )
>       1. Not sure if all these types are relevant for the industry today
>       2. AFAIK, TDM and SONET over packet are still widely deployed
>    2. Differentiation between Raw and Tagged Ethernet PW types (not sure
>    it is needed, but still)
>    3. All Interface Attributes listed in the IANA registry with the
>    following exclusions:
>       1. Interface MTU  (EVPN VPWS supports a standard way to ignore it
>       which IMHO is one great advantage over LDP-based signaling)
>       2. Flow Label (support is defined in 7432bis)
>    4. Full-blown PW status signaling
>    5. FCS retention – not sure it is used these days
>    6. PW fragmentation and reassembly - not sure it is used these days.
>
>
>
> Regards,
>
> Sasha
>
>
>
> Office: +972-39266302
>
> Cell:      +972-549266302
>
> Email:   Alexander.Vainshtein@rbbn.com
>
>
>
> *From:* Rabadan, Jorge (Nokia - US/Sunnyvale) <jorge.rabadan@nokia.com>
> *Sent:* Monday, May 30, 2022 1:02 PM
> *To:* Alexander Vainshtein <Alexander.Vainshtein@rbbn.com>; Stewart
> Bryant <stewart.bryant@gmail.com>; Andrew Alston - IETF <andrew-ietf=
> 40liquid.tech@dmarc.ietf.org>; mpls-chairs <mpls-chairs@ietf.org>
> *Cc:* SPRING WG <spring@ietf.org>; pals@ietf.org; bess@ietf.org
> *Subject:* Re: [Pals] [EXTERNAL] Re: [spring] Martini Pseudowires and SR
>
>
>
> I concur with Sasha.
>
> We’ve been gone through a significant effort to unify the service
> signaling by using EVPN. If we are missing anything in EVPN VPWS compared
> to T-LDP based PWs, I would rather look at extending EVPN VPWS (if needed).
> If not an option, it would good to discuss at least why EVPN VPWS is not an
> option.
>
>
>
> Thanks,
>
> Jorge
>
>
>
>
>
> *From: *Pals <pals-bounces@ietf.org> on behalf of Alexander Vainshtein <
> Alexander.Vainshtein@rbbn.com>
> *Date: *Monday, May 30, 2022 at 10:58 AM
> *To: *Stewart Bryant <stewart.bryant@gmail.com>, Andrew Alston - IETF <
> andrew-ietf=40liquid.tech@dmarc.ietf.org>, mpls-chairs <
> mpls-chairs@ietf.org>
> *Cc: *SPRING WG <spring@ietf.org>, pals@ietf.org <pals@ietf.org>,
> bess@ietf.org <bess@ietf.org>
> *Subject: *Re: [Pals] [EXTERNAL] Re: [spring] Martini Pseudowires and SR
>
> Stewart, Andrew and all,
>
> ++ Bess WG.
>
> I fully agree that using (targeted) LDP for setup of Martini PWs in an
> SR-based environment is quite problematic for the operators.
>
>
>
> One alternative is transition to setup of PWs using MP BGP based on the
> EVPN-VPWS mechanisms (RFC 8214
> <https://clicktime.symantec.com/3Qviu2KUub4f1w6MeHVbgcu6H4?u=https%3A%2F%2Fdatatracker.ietf.org%2Fdoc%2Fhtml%2Frfc8214>).
>
>
>
>
> These mechanisms probably require some extension to support PWs that carry
> non-Ethernet customer traffic as well as support of some features that can
> be signaled via LDP for Ethernet PWs but cannot be signaled today with
> EVPN-VPWS (e.g., FCS retention – RFC 4720
> <https://clicktime.symantec.com/32Jf7wnYMxKQPc3r3RR9Cy96H4?u=https%3A%2F%2Fdatatracker.ietf.org%2Fdoc%2Fhtml%2Frfc4720>
> ).
>
>
>
> My guess is that, once the basic EVPN-VPWS signaling is supported,
> migration of LDP-signaled PWs to EVPN-VPWS would be simple enough.
>
>
>
> This work, if approved, would require intensive cooperation between PALS
> WG and BESS WG.
>
>
>
> My 2c,
>
> Sasha
>
>
>
> Office: +972-39266302
>
> Cell:      +972-549266302
>
> Email:   Alexander.Vainshtein@rbbn.com
>
>
>
> *From:* Pals <pals-bounces@ietf.org> *On Behalf Of *Stewart Bryant
> *Sent:* Monday, May 30, 2022 11:10 AM
> *To:* Andrew Alston - IETF <andrew-ietf=40liquid.tech@dmarc.ietf.org>;
> pals@ietf.org; mpls-chairs <mpls-chairs@ietf.org>
> *Cc:* SPRING WG <spring@ietf.org>
> *Subject:* [EXTERNAL] Re: [Pals] [spring] Martini Pseudowires and SR
>
>
>
> Including the PALS and MPLS WGs in the discussion.
>
>
>
> In the case of PWs, LDP runs directly between the T-PEs to provide the
> control plane. If it is known that the only use of LDP is to support PW,
> then a lightweight profile of LDP might be implemented, ignoring unused
> parts, but this does not necessarily need a standard.
>
>
>
> Before you can profile LDP, you have to also profile PWs to determine
> which subset of the PW system you need to support. The danger here is that
> you end up going through the PW development cycle again as old requirements
> re-emerge.
>
>
>
> Stewart
>
>
>
>
>
>
>
> Sent from my iPad
>
>
>
> On 30 May 2022, at 07:22, Andrew Alston - IETF <
> andrew-ietf=40liquid.tech@dmarc.ietf.org> wrote:
>
> 
>
> Hi All,
>
>
>
> Sending this email wearing only the hat of a working group participant.
>
>
>
> One of the things that our network uses, and is used by so many networks
> out there, are martini based pseudowires (which for clarity are generally
> setup using what is described in RFC8077).  In an SR world however, this
> creates a problem, because typically you don’t want to run LDP in an SR
> context.  This means that standard martini pseudowires no longer function.
> This gets even more complicated when you want to do martini based
> pseudowires over an IPv6 only network, particularly considering the lack of
> widespread support for LDP6.
>
>
>
> This is also relevant in cases where networks wish to run SR-MPLS in the
> absence of SRv6 for whatever reason.
>
>
>
> So, my question to the working group is this:
>
>
>
> Is it worth looking at creating a form of LDP light – both compatible with
> IPv4 and IPv6 – that simply exists to setup and tear down the service
> labels for point to point services.  A form of targeted LDP without all the
> other complexities involved in LDP – that could potentially run at a lower
> preference than LDP itself (so if LDP is there, use it, if not use this)
>
>
>
> Before I start drafting though, I would like to hear from the working
> group if there are others who feel that this is worth doing and, call this
> a call for expressions of interest in those who may be willing to work
> towards something like this.  Happy to take emails on list or off list and
> see if we can find a solution.
>
>
>
> Looking forward to hearing from you all
>
>
>
> Thanks
>
>
>
> Andrew
>
>
>
>
>
>
>
> _______________________________________________
> spring mailing list
> spring@ietf.org
>
> https://clicktime.symantec.com/3Dg1AP6FnSDeshweMg29hXi7GS?u=https%3A%2F%2Fwww.ietf.org%2Fmailman%2Flistinfo%2Fspring
>
>
> Notice: This e-mail together with any attachments may contain information
> of Ribbon Communications Inc. and its Affiliates that is confidential
> and/or proprietary for the sole use of the intended recipient. Any review,
> disclosure, reliance or distribution by others or forwarding without
> express permission is strictly prohibited. If you are not the intended
> recipient, please notify the sender immediately and then delete all copies,
> including any attachments.
>
>
> Notice: This e-mail together with any attachments may contain information
> of Ribbon Communications Inc. and its Affiliates that is confidential
> and/or proprietary for the sole use of the intended recipient. Any review,
> disclosure, reliance or distribution by others or forwarding without
> express permission is strictly prohibited. If you are not the intended
> recipient, please notify the sender immediately and then delete all copies,
> including any attachments.
>
> Notice: This e-mail together with any attachments may contain information
> of Ribbon Communications Inc. and its Affiliates that is confidential
> and/or proprietary for the sole use of the intended recipient. Any review,
> disclosure, reliance or distribution by others or forwarding without
> express permission is strictly prohibited. If you are not the intended
> recipient, please notify the sender immediately and then delete all copies,
> including any attachments.
> _______________________________________________
> BESS mailing list
> BESS@ietf.org
> https://www.ietf.org/mailman/listinfo/bess
>