Re: [Idr] Fwd: [E] New Version Notification for draft-mishra-idr-v4-islands-v6-core-4pe-05.txt
Robert Raszuk <robert@raszuk.net> Mon, 31 July 2023 06:39 UTC
Return-Path: <robert@raszuk.net>
X-Original-To: idr@ietfa.amsl.com
Delivered-To: idr@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 5EA54C14CE33 for <idr@ietfa.amsl.com>; Sun, 30 Jul 2023 23:39:22 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.094
X-Spam-Level:
X-Spam-Status: No, score=-2.094 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, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_BLOCKED=0.001, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_REMOTE_IMAGE=0.01, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_BLOCKED=0.001, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=raszuk.net
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 4dsuW5Zre7EW for <idr@ietfa.amsl.com>; Sun, 30 Jul 2023 23:39:17 -0700 (PDT)
Received: from mail-lf1-x131.google.com (mail-lf1-x131.google.com [IPv6:2a00:1450:4864:20::131]) (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 90E50C14CE44 for <idr@ietf.org>; Sun, 30 Jul 2023 23:39:17 -0700 (PDT)
Received: by mail-lf1-x131.google.com with SMTP id 2adb3069b0e04-4fbf09a9139so6513825e87.2 for <idr@ietf.org>; Sun, 30 Jul 2023 23:39:17 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=raszuk.net; s=google; t=1690785555; x=1691390355; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=V+iobo3oyQAvG+KV1RfPYyQHXBNcafDViskdsKmzKEM=; b=eruD2IiF6ipy8tgNA0HUWn4PzCB1mfRefxgnaNsljqVZ0344RJdFUUFzjZUj37eeeS 7ifb8dROIBAQHbiG1T0f56v7edEXtQSgj+4JNm8/HuX6YYkwqnr/96gkm5TEOBgZYTK1 degDgJmSKPNCYJd+tvpdjRFVfVDC25WAplS6Z4QRwb/Hxm643sGNzpS4DlSWHYfDB/IB +EC456g/40V0kauJ4NvQIBKbCvMz59/cz9KZSrxxeGSWIDuMfDTwy72pxF/rd7swyydH og3iLMcBvgYdZCQ8UC0zN5Jy55f7M7ZVbxZMzyWS1tTR1TkYia208iEWXrDKNvOMz/8O Dw5A==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690785555; x=1691390355; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=V+iobo3oyQAvG+KV1RfPYyQHXBNcafDViskdsKmzKEM=; b=a1TFM0eImb68HoQy00FwyBZtfeUPUTnWtCKRsn4CbscV5c5RonuopQ13XppHq9+m1o 7OGp7RJI3czUrefqkgvFd2eT6EpSWZJpwSqrcE4P7GvxBWRCFsccMGNrpkv3ZpMgdArm qKHngwgwT+P9t6TOsdTiK3fLmRaChdRrke1l7shmyauzV/I4PVbzuaruKOW9kRI4psil +qaZx0LeMO5mwkqrD5YOfRT39CaRuJIFmhEwJVRi1hkcxOuZdC2oUKltI6gNpDqWIKso Vrh6fREnqP9d60kLmgyCFM+U7iRzfyHeo4439VuYx3Ns87woJT7Ui1RpcEJA5+kRMaCw n7XA==
X-Gm-Message-State: ABy/qLYkybYdP8ZRCslGm3XcrZnqaDzcKroHPk4qyGShMxC+l0xuhcC5 FSKMIPEjEteepumUq4keq7/tYXLTopk3viG9AgOpx1SZMi6Trpz3Bpg=
X-Google-Smtp-Source: APBJJlHujgQxgWyOR8NFVILF5ZvBL1GfSYQMWEDwOwkSN9kMLPUwYc+ggs+trtSG+tXlwWy9kRrcJQpNUbt12d8vvVE=
X-Received: by 2002:a05:6512:5ca:b0:4fe:3724:fdb1 with SMTP id o10-20020a05651205ca00b004fe3724fdb1mr831861lfo.41.1690785555044; Sun, 30 Jul 2023 23:39:15 -0700 (PDT)
MIME-Version: 1.0
References: <169047138994.3856.3652775004172582433@ietfa.amsl.com> <CAJhXr9_WbQ7N0qsR=8QdeBWG0_w31tpY-tm9=M+CeXtf6YO0nQ@mail.gmail.com> <CABNhwV3LGxQGUQhhoT-60imsyfVt62pMfSMg7USQ1ofxZXT2Rw@mail.gmail.com> <CAEfhRrz6_0Jj_HvoSeXH=4cfcNQQ_uy5FHZO8+FMeJfs4cuuVQ@mail.gmail.com> <CAOj+MMGSauMSaxgqX8j=bz=v0afcVk9qdX6t-X+v175qdc+y_A@mail.gmail.com> <CABNhwV32rZKYGYZ6adnGWWCpHfKzitd+9fZDWOHX5A6HziTqRA@mail.gmail.com> <CAOj+MMFgDBdkTU1fVc4Ty4zLj5WXKZ_JN=1hkrbsAA3Xwx6yEg@mail.gmail.com> <CABNhwV1dpaSpv6rh-E3jxr6q4oiWASA7g_xvYTfRTWJRifk9Uw@mail.gmail.com>
In-Reply-To: <CABNhwV1dpaSpv6rh-E3jxr6q4oiWASA7g_xvYTfRTWJRifk9Uw@mail.gmail.com>
From: Robert Raszuk <robert@raszuk.net>
Date: Mon, 31 Jul 2023 08:39:04 +0200
Message-ID: <CAOj+MMGzwzCJ_hHpyOQ349wt5iBNbOCHr89=Gk+Xts8-S3nw8Q@mail.gmail.com>
To: Gyan Mishra <hayabusagsm@gmail.com>
Cc: IDR List <idr@ietf.org>, Igor Malyushkin <gmalyushkin@gmail.com>, idr-chairs <idr-chairs@ietf.org>
Content-Type: multipart/alternative; boundary="0000000000006674610601c2b014"
Archived-At: <https://mailarchive.ietf.org/arch/msg/idr/tpcZtbXAzXBQWqzZaMAECvvZYII>
Subject: Re: [Idr] Fwd: [E] New Version Notification for draft-mishra-idr-v4-islands-v6-core-4pe-05.txt
X-BeenThere: idr@ietf.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: Inter-Domain Routing <idr.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/idr>, <mailto:idr-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/idr/>
List-Post: <mailto:idr@ietf.org>
List-Help: <mailto:idr-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/idr>, <mailto:idr-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 31 Jul 2023 06:39:22 -0000
Gyan, *> Arbitrary label versus explicit null debate for IPv6 LSP.* "debate" - but still configuration option. Vendor's manual: You can configure the IPv6 Explicit Null Label by using the label mode [ explicit-null| all-explicit-null] command in the address family configuration mode. *> Keeping the IPv4 prefixes labeled versus unlabeled * Clearly a configuration choice. *> Label stack depth and future MNA* Result of configuration choice *> Support for PHP or not * See vendor's manual explicit null vs implicit null configuration *> Support for explicit null or not * Again as per line #1 - configuration choice *> 4PE data planes supported * Again configuration option. Hint: You may have IPv4 VRF on IPv6 node. *> Support for LDP and RSVP-TE * Configuration choice Thank you, R. On Mon, Jul 31, 2023 at 8:28 AM Gyan Mishra <hayabusagsm@gmail.com> wrote: > > Robert > > I don’t think any of them are configuration options as they are 4PE > specification design options. > > Kind Regards > > Gyan > > On Mon, Jul 31, 2023 at 2:25 AM Robert Raszuk <robert@raszuk.net> wrote: > >> Gyan, >> >> All of the below elements are configuration options for already defined >> standards track RFCs >> >> Last time I checked IDR nor any other IETF WG is not tasked to >> standardize specific configuration choices. >> >> Kind regards, >> Robert >> >> >> On Mon, Jul 31, 2023 at 7:47 AM Gyan Mishra <hayabusagsm@gmail.com> >> wrote: >> >>> >>> Hi Robert >>> >>> As I had mentioned during the IDR meeting update and exactly the >>> discussion being had with Igor that there are a lot of procedural details >>> in the draft that if not standardized could result in interoperability >>> issues. >>> >>> RFC 4798 6PE was standardized and for good reason and following suit >>> here to provide vendor interoperability this 4PE draft should be >>> standardized. >>> >>> A few items from this discussion thread that are good reasons for >>> standardization. >>> >>> Arbitrary label versus explicit null debate for IPv6 LSP. >>> >>> Keeping the IPv4 prefixes labeled versus unlabeled >>> >>> Label stack depth and future MNA >>> >>> Support for PHP or not >>> >>> Support for explicit null or not >>> >>> 4PE data planes supported >>> >>> Support for LDP and RSVP-TE >>> >>> Let the WG decide during the adoption call but I don’t think there is >>> any reason why this should not be standardized. >>> >>> Thanks for the comments! >>> >>> Gyan >>> >>> On Sun, Jul 30, 2023 at 3:45 PM Robert Raszuk <robert@raszuk.net> wrote: >>> >>>> Hi, >>>> >>>> Great comments from Igor. >>>> >>>> And honestly I do not intend to repeat again the entire discussion on >>>> this document we already have had in the past. >>>> >>>> But please Gyan kindly answer why you think this draft should be a >>>> "Standards Track" document. You are not defining a single >>>> protocol extension nor providing modifications to protocol operations. You >>>> are also not asking IANA for any new type or value allocation. >>>> >>>> Instead the draft enumerates various ways one could in theory signal >>>> IPv4 reachability over networks running IPv6 in the underlay. >>>> >>>> And that list of options is also far from complete too as it misses the >>>> number of various overlays one can build today to transparently communicate >>>> over any underlay and over any provider without any action on the transit >>>> network. Think of it like CSC with pure IPv6 encapsulation - no labels nor >>>> SIDs of any sort needed. >>>> >>>> So considering the above easy alternative it can't fit to be a BCP doc >>>> as provided options in the draft are neither "Best" nor "Common" and hardly >>>> "Practices" :). >>>> >>>> Honestly what could be perhaps helpful (if authors are still interested >>>> in this topic) instead of 24 pages of pretty hard to parse text a single >>>> 1-2 page table comparing pros and cons of various solutions in this space >>>> published as an informational RFC. >>>> >>>> Kind regards, >>>> Robert >>>> >>>> >>>> On Sun, Jul 30, 2023 at 2:40 PM Igor Malyushkin <gmalyushkin@gmail.com> >>>> wrote: >>>> >>>>> Hi Gyan, >>>>> >>>>> I have several questions w.r.t your draft. But first I would like to >>>>> clarify some points from your summary. >>>>> >>>>> >>>>> "*Customer IPv4 prefixes must be labeled when tunneled over IPv6 LSP*". >>>>> I believe there is a misconception between the "labeled prefixes" and the >>>>> "labeled traffic". Prefixes cannot be tunneled via LSPs, traffic can be. >>>>> Customer IPv4 prefixes can be dissipated as vanilla IPv4 prefixes without >>>>> labels. I described the reasons during the previous discussion of this >>>>> document. >>>>> >>>>> "*If not labeled on the PHP node when the topmost label is popped the >>>>> native IPv4 prefix is exposed and is not routable and will be dropped*", >>>>> this sentence describes traffic, not BGP prefixes, and I'm sure we can >>>>> reach the goal of having two and more labels in a stack without advertising >>>>> tons of IPv4 reachability with labels. We can solely use IPv4 labeled >>>>> prefixes also, as this draft describes, but there are other options too. >>>>> >>>>> "*RFC 7948 “6PE” states that the label bound to the IPv4 prefixes may >>>>> be an arbitrary value or explicit null label which has led to vendor >>>>> interoperability issues in the past*". Can you please elaborate on >>>>> that topic? I know the exact opposite cases. >>>>> >>>>> "*4PE draft states that the IPv4 prefixes must use MPLS QOS RFC 3270 >>>>> Pipe mode explicit null label bound to the IPv4 prefix and MUST be used ...*". >>>>> In my opinion, the idea of getting rid of arbitrary labels breaks a lot of >>>>> stuff. I will clarify it later. >>>>> >>>>> "*Additional text clarity added related RFC 8950 next hop encoding...*". >>>>> Honestly, I don't understand why. It is just a rephrase of the stuff from >>>>> the original standard. Can you shed light on the necessity of this section? >>>>> Maybe I'm missing something. >>>>> >>>>> Here and after my comments w.r.t the body of the draft. >>>>> >>>>> 1. Section 1. "*This document explains the "4PE" design procedures >>>>> and how to interconnect IPv4 islands over a Multiprotocol Label Switching >>>>> (MPLS) [RFC3031] LDPv6 enabled IPv6-Only core, Segment Routing (SR) enabled >>>>> SR-MPLS [RFC8660] IPv6-Only core or SRv6 [RFC8986] IPv6-Only core*". >>>>> Is my understanding correct that the 4PE solution does not support RSVP-TE >>>>> LSP signaled to IPv6 tail-ends over an IPv6-routed core? I see LDPv6 here, >>>>> but the link goes to RFC3031 which is the architecture standard that >>>>> applies not only to LDP. By the way, 6PE/6vPE perfectly works with RSVP >>>>> LSPs. >>>>> >>>>> 2. Section 1. "*The 4PE routers exchange the IPv4 reachability >>>>> information transparently over the core using the Multiprotocol Border >>>>> Gateway Protocol (MP-BGP) over IPv6. In doing so, the BGP Next Hop field >>>>> egress PE FEC (Forwarding Equivalency Class) is used to convey the IPv6 >>>>> address of the 4PE router learned dynamically via IGP...*". Can a 4PE >>>>> router, that resides in one IGP domain, use a next-hop address received >>>>> from the other domain via, for example, IPv6 labeled unicast? >>>>> >>>>> 3. Section 1. "...* over an MPLS [RFC3031] LDP IPv6 core, Segment >>>>> Routing SR-MPLS [RFC8660] IPv6 core or SRv6 [RFC8986] IPv6 core*". >>>>> This part is a repetition of the same that was done previously, and it will >>>>> be repeated several times later. Moreover, there are standard numbers >>>>> enclosed after every term again and again. As I understand, it is enough to >>>>> do it one time per every desired abbreviation during the whole body. >>>>> >>>>> 4. Section 1. "*The approach requires that the Provider Edge (PE) >>>>> routers Provider Edge - Customer Edge (PE-CE) connections to Customer Edge >>>>> (CE)*". Honestly, it is difficult to read such things. From my POV, >>>>> there should be a section with all unique definitions pertaining to this >>>>> draft (e.g., 4PE router). Moreover, things such as the PE, and CE are >>>>> well-known and do not require unfolding. There is a document of such >>>>> well-known terms on the IETF portal for your convenience. The last thing, >>>>> as I see the same abbreviations are unfolded many times during the >>>>> document, which is contrary to the idea of an abbreviation in general. Once >>>>> explained, an abbreviation should be used without further explanation. >>>>> >>>>> 5. Section 3. "*...the 4PE IPv6 address Loopback0 MUST to be routable >>>>> within the IPv6 core*". What is "the 4PE IPv6 address Loopback0"? It >>>>> was not previously defined in the document. >>>>> >>>>> 6. Section 3. "*Every ingress 4PE router can signal an IPv6 MPLS >>>>> [RFC3031] LSP, SRMPLS [RFC8660] LSP or instantiate an SRv6 Best Effort (BE) >>>>> or Segment Routing Traffic Engineering (SR-TE) [RFC9256] path to send to >>>>> any egress 4PE router*". It is not necessary for an ingress router to >>>>> signal an LSP. For example, LDP DU signals LSPs from a downstream towards >>>>> all possible upstreams. RSVP or LDP DoD acts the opposite (if we talk about >>>>> the intention, not a label distribution). So it is better to rephrase this >>>>> sentence as "every ingress 4PE router can have an LSP toward..." or >>>>> something like that. >>>>> >>>>> 7. Section 3. "*...the IPv6 signaled next hop Loopback0 used to >>>>> identify the Ingress and Egress 4PE router*". Now the Loopback0 is >>>>> somehow connected to some next-hop. I believe this connection should be >>>>> clarified too. >>>>> >>>>> 8. Section 3. "*In doing so, the 4PE routers convey their IPv6 >>>>> address FEC label binding as the BGP Next Hop for the advertised IPv4 >>>>> prefixes*". The term FEC is pretty general, but the "IPv6 address FEC >>>>> label binding" can mislead a reader. From my POV, this term is related to >>>>> LDP, but the document includes many options to signal transport paths. >>>>> >>>>> 9. Section 3. "*The ingress and egress 4PE router MUST bind a label >>>>> to the IPv4 prefix as per [RFC8277] using BGP Labeled Unicast herinafter >>>>> called BGP-LU, AFI/SAFI Address Family (AFI) / Subsequent Address Family >>>>> Identifier (SAFI) 2-tuple "1/4"*". Which is the IPv4 prefix? If I >>>>> understand it correctly, this requirement is too strict. As a designer I >>>>> don't want to send all IPv4 prefixes with labels in every case, I want to >>>>> have some flexibility. Moreover, as a part of the implementation team, I'm >>>>> sure we won't consider this as the only possible option too. >>>>> >>>>> 10. Section 3. "*The Ingress 4PE router MUST forward IPv4 NLRI as >>>>> Labeled prefixes using BGP-LU SAFI over the IPv6-signaled LSP towards the >>>>> Egress 4PE router identified by the IPv4 address advertised in the IPv6 >>>>> next hop encoding per [RFC8950]*". NLRI is a term related to BGP >>>>> message encoding. How can a 4PE router forward an NLRI over an LSP? >>>>> Forwarding is a procedure of transmitting traffic, LSP is a transport >>>>> entity used for forwarding labeled traffic, not NLRIs. >>>>> >>>>> 11. Section 4. "*To ensure interoperability between routers that >>>>> implement the 4PE design over MPLS [RFC3031] LDP IPv6 Core described in >>>>> this document, ingress and egress 4PE MUST support building the underlay >>>>> tunneling using IPv6-signaled MPLS LSPs established by LDP [RFC5036] or >>>>> Resource Reservation Protocol (RSVP-TE) [RFC3209]*". Here we see that >>>>> RSVP is anyhow possible, but I'm still missing the idea of "MPLS LDP IPv6 >>>>> Core" and how RSVP is related to it. Is this sentence about LDP over RSVP >>>>> tunneling? Or about ships in the night? >>>>> >>>>> 12. Section 4. "*The (outer) label imposed MUST correspond to the >>>>> IPv6- signaled LSP starting on the ingress 4PE Router and ending on the >>>>> egress 4PE Router*". What if I have segmented LSPs among several >>>>> domains of the same AS? Pretty sure that in this case, the outermost label >>>>> would correspond to an LSP either from an ingress 4PE to an ABR or from an >>>>> ABR to the other ABR/egress 4PE router. >>>>> >>>>> 13. Section 4. "*The reason for the use of a second level bottom of >>>>> stack service label...*". I'm sure that the stack can be deeper. I >>>>> made some hints earlier in my notes (e.g., see the previous bullet), also >>>>> you can think about emerging MNA solutions. I think it is better to pay >>>>> attention not to the number of labels in a stack but to the fact that the >>>>> bottom label must pertain to an LSP forwarding IPv4 traffic and that this >>>>> label must be present on the egress. >>>>> >>>>> 14. Section 4. "*...it allows for Penultimate Hop Popping (PHP) on >>>>> the IPv6 Label Switch Router (LSR) Provider (P) node,...*". I believe >>>>> it is better to use one terminology, either pertaining to an MPLS LSP >>>>> (LER/LSR) or a BGP service (P/PE) in a single sentence. Here MPLS-related >>>>> terms suit you better because you are describing an LSP and label stack. >>>>> >>>>> 15. Section 4. "*The label advertised by the egress 4PE Router with >>>>> MP-BGP MUST be an explicit Null label Pipe mode Diff-Serv Tunneling Model >>>>> use case as defined in [RFC3270], so that the topmost label can be >>>>> preserved Ultimate Hop POP (UHP) to the egress PE Edge LSR*". Why can >>>>> it be an arbitrary label instead an explicit null? >>>>> >>>>> 16. Section 4. "*The explicit null label advertised by the egress PE >>>>> router with MP-BGP also identifies the IPv4 routing context or outgoing >>>>> interface to forward the packet to and ingress 4PE Router which MUST be >>>>> able to be accept the "IPv6 Explicit NULL Label" advertised*". From >>>>> the very beginning of this statement, I understand that the egress PE >>>>> advertises an explicit label (0) for IPv4-labeled unicast routes to >>>>> identify either IPv4 routing context or outgoing interface. The end of this >>>>> sentence tells us that the ingress 4PE router must accept the IPv6 explicit >>>>> label (2). This label (2) cannot be used to identify either IPv4 routing >>>>> contexts or any interfaces. So I made an assumption that there is a mistake >>>>> and this is actually a 0 label, not 2. >>>>> How can the label with the same value (0) identify several things >>>>> (context, interface)? If you offer to bind this label to an exact interface >>>>> (without a route lookup at egress) instead of doing a lookup in the global >>>>> routing context/table, it will break the idea behind this special purpose >>>>> label and won't support more than one interface for your solution. >>>>> Arbitrary labels solve this issue and also many others. >>>>> For example, it allows us to do EPE if and only if we dissipate IPv4 >>>>> reachability (separately from its next-hop addresses) as IPv4 routes with >>>>> IPv4 next-hops alongside arbitrary labels for these next-hops distributed >>>>> as labeled IPv4 routes with IPv6 next-hops (which this draft does not >>>>> support and breaks). In this case, these arbitrary labels are allocated in >>>>> per next-hop fashion and preclude any IP lookups at egress. I've have >>>>> mentioned it several months ago. >>>>> >>>>> 17. Section 4. "*4PE design MUST use "IPv6 Explicit Null label" value >>>>> 2 defined in [RFC4182] Pipe Diff-Serv Tunneling Model as defined in >>>>> [RFC3270]*". From this statement, I conclude that the authors talk >>>>> about an underlying transport (IPv6 LSP via BGP LU). Why does the draft >>>>> about a service mandate a label for transport? I don't see anything wrong >>>>> with arbitrary labels for underlying IPv6 LSPs either. If you want to >>>>> highlight that there should *not *be PHP it does not mean there is >>>>> only option is an explicit label. Some vendors use arbitrary labels by >>>>> default with an option to use a label of 2 instead. >>>>> >>>>> 18. Section 4. "*BGP/MPLS VPN [RFC4364] defines 3 label allocation >>>>> modes for Layer 3 VPN's...*" and later "*The 4PE design provides the >>>>> same operator flxeiblity as BGP/MPLS VPN [RFC4798], 2 level label stack >>>>> option using Per-CE label allocation mode where the next hop is label so >>>>> all prefixes associated with CE get the same label. The 4PE design provides >>>>> the same operator flxeiblity as BGP/MPLS VPN [RFC4798], 2 level label stack >>>>> option using Per-VRF label allocation mode where all prefixes within a VRF >>>>> get the same is label*". I believe it is not possible with an >>>>> explicit label for an IPv4 LSP either because a single value cannot be >>>>> attached to many different things at the same time. >>>>> >>>>> 19. Section 7.3.1. "*...the 4PE IPv4 BGP-LU labeled Unicast RIB is >>>>> not maintained on the ASBR*". I would further elaborate on this point >>>>> as these routes must not be installed in the forwarding table as some >>>>> vendors do it by default because it breaks the whole idea of the Option B >>>>> scenario. Only their labels must be installed into LFIB. With the VPN-based >>>>> option B there is no any danger because we do not create VRFs on an ASBR, >>>>> but with labeled unicast this is a possible issue. >>>>> >>>>> 20. Section 8. RFC 8950 describes the logic of how to handle next-hop >>>>> addresses with different lengths including the routes of SAFI 4. Does this >>>>> section bring something new? >>>>> >>>>> 21. I don't see any description of a scenario when some vendors >>>>> install specific routes in auxiliary tables for the sake of further BGP NH >>>>> resolution and consider them as LSPs. There should be a warning at least. >>>>> Let's imagine a case where there are two or more BNG routes residing >>>>> in a single PoP. The core network is single-stack IPv6. BNGs are >>>>> dual-stacked because we are still supporting some legacy connections for v4 >>>>> eyeballs. PE routes that are connected to these BNGs are dual-stacked too >>>>> (you can consider a BNG as a CE router). Now we want to distribute tons of >>>>> /32 among PEs because the BNGs share the same IPv4 subnets. That >>>>> facilitates more optimal allocation of the depleting IPv4 address space and >>>>> is a pretty common case in the SP world. So, if the PE routers distribute >>>>> these specifics by mistake or by design (let's say, to other PEs of this >>>>> PoP for CG-NAT purposes) as IPv4 labeled unicast routes. Possible receivers >>>>> of these routes may consider them viable LSPs. Imagine of hundreds >>>>> thousands of such prefixes. That's actually another reason why labeled >>>>> unicast is not good at this task. >>>>> >>>>> >>>>> Thank you in advance. >>>>> Igor. >>>>> >>>>> чт, 27 июл. 2023 г. в 19:50, Gyan Mishra <hayabusagsm@gmail.com>: >>>>> >>>>>> All >>>>>> >>>>>> I have updated the IDR draft below updates as reviewed during our >>>>>> IETF 117 meeting. >>>>>> >>>>>> >>>>>> https://datatracker.ietf.org/doc/draft-mishra-idr-v4-islands-v6-core-4pe/05/ >>>>>> >>>>>> >>>>>> - Customer IPv4 prefixes must be labeled when tunneled over IPv6 >>>>>> LSP. If not labeled on the PHP node when the topmost label is popped the >>>>>> native IPv4 prefix is exposed and is not routable and will be dropped >>>>>> unless RFC 3270 Pipe mode explicit null signaling is enabled, which may not >>>>>> be always the case for customers wanting to use PHP signaling implicit >>>>>> null. For IPv6 prefixes over an IPv6 core or IPv4 prefixes over IPv4 core >>>>>> at PHP node the IPv4 or IPv6 prefix can still be routed since the protocol >>>>>> of the tunneled prefix matches underlay protocol. Not the case for 4PE >>>>>> with protocol mismatch between 2 level label stack topmost IPv6 label and >>>>>> BOS S bit IPv4 prefixes. >>>>>> - Label stack MUST be 2 Level Label Stack is only supported. >>>>>> This is for interoperability as additional labels could be added for >>>>>> flexibility to the specification but that could break interop. IPv4 >>>>>> prefixes must still be labeled even with MPLS QOS explicit null label pipe >>>>>> mode RFC 3270 as described in RFC 3032. >>>>>> - RFC 7948 “6PE” states that the label bound to the IPv4 prefixes >>>>>> may be an arbitrary value or explicit null label which has led to vendor >>>>>> interoperability issues in the past. 4PE draft states that the IPv4 >>>>>> prefixes must use MPLS QOS RFC 3270 Pipe mode explicit null label bound to >>>>>> the IPv4 prefix and MUST be used to signal from egress 4PE to ingress 4PE >>>>>> router that the packet is an IPv4 packet to identify the IPv4 routing >>>>>> context or outgoing interface to forward the packet. >>>>>> - When RFC 7948 “6PE” was written when Segment Routing did not >>>>>> exist. The 4PE draft provides a detailed interworking of how 4PE is >>>>>> implemented with Segment Routing both SR-MPLS & SRv6. I have cleaned up >>>>>> the related text in the draft on Segment Routing support to make it more >>>>>> clear. >>>>>> - Additional text clarity added related RFC 8950 next hop >>>>>> encoding interaction with 4PE and the importance of 4PE procedures and that >>>>>> RFC 8950 is strictly about the next hop encoding of IPv4 NLRI over an IPv6 >>>>>> next hop peer. >>>>>> - Added comments related to alternatives to 4PE that exist to >>>>>> connect IPv4 islands over an IPv6 core and why a standardized BGP based 4PE >>>>>> specification is the desired solution as compared to alternatives that >>>>>> exist today. >>>>>> >>>>>> >>>>>> Please review and provide any comments. >>>>>> >>>>>> Thank you >>>>>> >>>>>> Gyan >>>>>> >>>>>> >>>>>> >>>>>> ---------- Forwarded message --------- >>>>>> From: <internet-drafts@ietf.org> >>>>>> Date: Thu, Jul 27, 2023 at 11:23 AM >>>>>> Subject: [E] New Version Notification for >>>>>> draft-mishra-idr-v4-islands-v6-core-4pe-05.txt >>>>>> To: Adam Simpson <adam.1.simpson@nokia.com>, Gyan Mishra < >>>>>> gyan.s.mishra@verizon.com>, Jeff Tantsura <jefftant.ietf@gmail.com>, >>>>>> Mankamana Mishra <mankamis@cisco.com>, Shuanglong Chen < >>>>>> chenshuanglong@huawei.com>, Sudha Madhavi <smadhavi@juniper.net> >>>>>> >>>>>> >>>>>> >>>>>> A new version of I-D, draft-mishra-idr-v4-islands-v6-core-4pe-05.txt >>>>>> has been successfully submitted by Gyan Mishra and posted to the >>>>>> IETF repository. >>>>>> >>>>>> Name: draft-mishra-idr-v4-islands-v6-core-4pe >>>>>> Revision: 05 >>>>>> Title: Connecting IPv4 Islands over IPv6 Core using IPv4 >>>>>> Provider Edge Routers (4PE) >>>>>> Document date: 2023-07-27 >>>>>> Group: Individual Submission >>>>>> Pages: 24 >>>>>> URL: >>>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__www.ietf.org_archive_id_draft-2Dmishra-2Didr-2Dv4-2Dislands-2Dv6-2Dcore-2D4pe-2D05.txt&d=DwICaQ&c=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ&r=DnUkF34wu4mqq0UY8nn2rxBBO7qOW_D-RfNVLML28ZU&m=VzHwh1TdZ13EhVmr48yMIBUCBRJ2ddcFx1t6Q7ZRm5rIAdubltLbXN5rM-19Gpnf&s=nt2Ly9ZOC094SqRgkAoslAoIF6Pp9RgKbxqqksJcfI4&e= >>>>>> Status: >>>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__datatracker.ietf.org_doc_draft-2Dmishra-2Didr-2Dv4-2Dislands-2Dv6-2Dcore-2D4pe_&d=DwICaQ&c=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ&r=DnUkF34wu4mqq0UY8nn2rxBBO7qOW_D-RfNVLML28ZU&m=VzHwh1TdZ13EhVmr48yMIBUCBRJ2ddcFx1t6Q7ZRm5rIAdubltLbXN5rM-19Gpnf&s=DJfC1DqgQ5IVWI3g7_N3FAyCnmJzFOeSCg3YcxYobjw&e= >>>>>> Htmlized: >>>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__datatracker.ietf.org_doc_html_draft-2Dmishra-2Didr-2Dv4-2Dislands-2Dv6-2Dcore-2D4pe&d=DwICaQ&c=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ&r=DnUkF34wu4mqq0UY8nn2rxBBO7qOW_D-RfNVLML28ZU&m=VzHwh1TdZ13EhVmr48yMIBUCBRJ2ddcFx1t6Q7ZRm5rIAdubltLbXN5rM-19Gpnf&s=F_Wr8Fgqdm8T5fOlOYkhpHlYyUs3dJU1xXOA9ouUDTU&e= >>>>>> Diff: >>>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__author-2Dtools.ietf.org_iddiff-3Furl2-3Ddraft-2Dmishra-2Didr-2Dv4-2Dislands-2Dv6-2Dcore-2D4pe-2D05&d=DwICaQ&c=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ&r=DnUkF34wu4mqq0UY8nn2rxBBO7qOW_D-RfNVLML28ZU&m=VzHwh1TdZ13EhVmr48yMIBUCBRJ2ddcFx1t6Q7ZRm5rIAdubltLbXN5rM-19Gpnf&s=fTNPBdbUKuSCsofECeey7RGCd80t507kdsJP931effo&e= >>>>>> >>>>>> Abstract: >>>>>> As operators migrate from an IPv4 core to an IPv6 core for global >>>>>> table internet routing, the need arises to be able provide routing >>>>>> connectivity for customers IPv4 only networks. This document >>>>>> provides a solution called 4Provider Edge, "4PE" that connects IPv4 >>>>>> islands over an IPv6-Only Core Underlay Network. >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> The IETF Secretariat >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> >>>>>> <http://www.verizon.com/> >>>>>> >>>>>> *Gyan Mishra* >>>>>> >>>>>> *IT Technologist & Innovations Specialist* >>>>>> >>>>>> *Associate Fellow-Network Design* >>>>>> >>>>>> *Network Solutions A**rchitect, * >>>>>> >>>>>> *R&S, SP SME & Protocol Design Expert* >>>>>> >>>>>> *Global Technology Services* >>>>>> >>>>>> >>>>>> >>>>>> *O 240 970-6287M 301 502-1347* >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> >>>>>> <http://www.verizon.com/> >>>>>> >>>>>> *Gyan Mishra* >>>>>> >>>>>> *Network Solutions A**rchitect * >>>>>> >>>>>> *Email gyan.s.mishra@verizon.com <gyan.s.mishra@verizon.com>* >>>>>> >>>>>> >>>>>> >>>>>> *M 301 502-1347* >>>>>> >>>>>> _______________________________________________ >>>>>> Idr mailing list >>>>>> Idr@ietf.org >>>>>> https://www.ietf.org/mailman/listinfo/idr >>>>>> >>>>> _______________________________________________ >>>>> Idr mailing list >>>>> Idr@ietf.org >>>>> https://www.ietf.org/mailman/listinfo/idr >>>>> >>>> -- >>> >>> <http://www.verizon.com/> >>> >>> *Gyan Mishra* >>> >>> *Network Solutions A**rchitect * >>> >>> *Email gyan.s.mishra@verizon.com <gyan.s.mishra@verizon.com>* >>> >>> >>> >>> *M 301 502-1347* >>> >>> -- > > <http://www.verizon.com/> > > *Gyan Mishra* > > *Network Solutions A**rchitect * > > *Email gyan.s.mishra@verizon.com <gyan.s.mishra@verizon.com>* > > > > *M 301 502-1347* > >
- [Idr] Fwd: [E] New Version Notification for draft… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Robert Raszuk
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Robert Raszuk
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Robert Raszuk
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Robert Raszuk
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra
- Re: [Idr] Fwd: [E] New Version Notification for d… Igor Malyushkin
- Re: [Idr] Fwd: [E] New Version Notification for d… Gyan Mishra