Re: [nvo3] Working Group Last Call and IPR Poll for draft-ietf-nvo3-geneve-oam-07

[Greg Mirsky <[e-mail]>]

Hi Xiao Min,
thank you for your thorough review. Please find my notes below tagged
GIM3>>. Attached, please find the updated working version .

Regards,
Greg

On Mon, Oct 30, 2023 at 11:49 PM <[e-mail]> wrote:

> Hi Greg,
>
>
> Thank you for the reply and proposed updates.
>
> Please see inline with [XM-3]>>>.
>
>
> Original
> *From: *GregMirsky <[e-mail]>
> *To: *肖敏10093570;
> *Cc: *[e-mail] <[e-mail]>;[e-mail] <
> [e-mail]>;[e-mail] <[e-mail]>;
> [e-mail] <[e-mail]>;
> *Date: *2023年10月26日 10:43
> *Subject: **Re: [nvo3] Working Group Last Call and IPR Poll for
> draft-ietf-nvo3-geneve-oam-07*
> _______________________________________________
> nvo3 mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/nvo3
>
> Hi Xiao Min,
> thank you for your thoughtful consideration of the proposed changes and
> the proposed update. I've accepted your idea with a minor editorial
> modification:
> OLD TEXT:
>    In the first case, a communication problem between Network
>    Virtualization Edge (NVE) device A and NVE C was observed.  The
>    underlay, e.g., IP network, forwarding is working well but the Geneve
>    connection is unstable for all tenants of NVE A and NVE C.
>    Troubleshooting and localization of the problem can be done
>    irrespective of the VNI value.
> NEW TEXT:
>    In the first case, consider when a communication problem
>    between Network Virtualization Edge (NVE) device A and NVE C exists.
>    Upon the investigation, the operator discovers that the forwarding in
>    the underlay, e.g., the IP network, is working well.  Still, the
>    Geneve connection is unstable for all NVE A and NVE C tenants.
>    Detection, troubleshooting, and localization of the problem can be
>    done irrespective of the VNI value.
> [XM-3]>>> It looks good to me.
>
>
> I hope that you agree with the new version. Attached, please find the new
> working version of the draft and the diff highlighting all the updates.
>
> [XM-3]>>> It seems some of my previous comments are missed. Repeat them as
> below.
>
> In Section 2, it says "In the latter case, the test packet MUST use the same Geneve encapsulation as the data packet (except for the value in the Protocol Type field [RFC8926]), including the value in the Virtual Network Identifier (VNI) field." Why does it say "except for the value in the Protocol Type field [RFC8926]"? I don't think so.
>
> GIM3>> If the value of the Protocol Type field indicates Ethernet payload
(0x6558), then IPv4 or IPv6 encapsulated OAM packets must be identified by
a different respective values in the Protocol Type field. Wou;d you agree?

>
> In Section 2.1, it says "The ICMP echo reply is encapsulated in Geneve as specified in Section 2.2...", that's incorrect, do you mean Section 3?
>
> GIM3>> I think that the reference to Section 2.2 is correct as that
section defines the encapsulation of an OAM packet in Geneve using the
Management VNI. Section 3 only lists references to the relevant RFCs.

> In Section 2.2, it says "Active OAM in Geneve network uses an IP encapsulation", lacking the context of the Management VNI case.
>
> GIM3>> Would the following update make that clear:
OLD TEXT:
  Active OAM in Geneve network uses an IP encapsulation.
NEW TEXT:
   Active OAM over a Management VNI in the Geneve network uses an IP
   encapsulation.

In Section 2.2, it says "The UDP source port can be used to provide
entropy...", I don't think so.
>
> GIM3>> I agree, this is unnecessary as active OAM will use the same
entropy mechanisms as the Geneve data flow.

> In Section 2.2, it says "Destination IP: IP address MUST NOT be of one of tenant's IP addresses. The IP address MUST be set to the loopback address 127.0.0.1/32 for IPv4, or the loopback address ::1/128 for IPv6 [RFC4291]." Now that "the IP address MUST be set to the loopback address", why does it need to say "IP address MUST NOT be of one of tenant's IP addresses"?
>
> GIM3>> Thank you for pointing that out. I agree, "MUST NOT" is unnecessary
as "MUST be set to the loopback address" is sufficient.

>
> Cheers,
>
> Xiao Min
>
>
> Regards,
> Greg
>
> On Mon, Oct 16, 2023 at 8:07 PM <[e-mail]> wrote:
>
>> Hi Greg,
>>
>>
>> Thank you for the reply.
>>
>> Please see inline with [XM-2]>>>.
>> Original
>> *From: *GregMirsky <[e-mail]>
>> *To: *肖敏10093570;
>> *Cc: *[e-mail] <[e-mail]>;[e-mail] <
>> [e-mail]>;[e-mail] <[e-mail]>;
>> [e-mail] <[e-mail]
>> >;
>> *Date: *2023年10月12日 22:01
>> *Subject: **Re: [nvo3] Working Group Last Call and IPR Poll for
>> draft-ietf-nvo3-geneve-oam-07*
>> Hi Xiao Min,
>> thank you for your clarifications and detailed questions. Please find my
>> notes below tagged by GIM2>>. Also, attached in the new working version and
>> diff highlighting updates.
>>
>> Regards,
>> Greg
>>
>> On Sat, Oct 7, 2023 at 9:46 AM <[e-mail]> wrote:
>>
>>> Hi Greg,
>>>
>>>
>>> Many thanks for your consideration of my comments.
>>>
>>> I noticed that a new -08 version has been posted, so my further comments
>>> would be based on the latest revision.
>>>
>>> Please see inline.
>>> Original
>>> *From: *GregMirsky <[e-mail]>
>>> *To: *肖敏10093570;
>>> *Cc: *[e-mail] <[e-mail]>;[e-mail] <
>>> [e-mail]>;[e-mail] <[e-mail]>;
>>> [e-mail] <[e-mail]
>>> >;
>>> *Date: *2023年09月22日 09:09
>>> *Subject: **Re: [nvo3] Working Group Last Call and IPR Poll for
>>> draft-ietf-nvo3-geneve-oam-07*
>>> _______________________________________________
>>> nvo3 mailing list
>>> [e-mail]
>>> https://www.ietf.org/mailman/listinfo/nvo3
>>>
>>> Hi Xiao Min,
>>> thank you for your detailed comments and thoughtful suggestions. Please
>>> find my notes below tagged GIM>>. Attached are the new working version of
>>> the draft and the diff highlighting the updates.
>>>
>>> Regards,
>>> Greg
>>>
>>> On Mon, Aug 14, 2023 at 7:12 PM <[e-mail]> wrote:
>>>
>>>> Hi Greg,
>>>>
>>>>
>>>> Thanks for taking my suggestions into account. I believe this document
>>>> is on the right way.
>>>>
>>>> Still, I want to extract some text from the working version for further
>>>> discussion.
>>>>
>>>> In section 2.1, it says "Encapsulation of test packets for both cases
>>>> is discussed in Section 2.2."
>>>>
>>>> As I've said before, the OAM over Geneve encap defined in section 2.2
>>>> applies *only* to the Management VNI, i.e., the first case.
>>>>
>>> GIM>> I agree and removed this new sentence appending the following
>>> sentence to the paragraph that introduces the Management VNI:
>>> NEW TEXT:
>>>    Encapsulation of
>>>
>>>    test packets using the Management VNI is discussed in Section 2.2.
>>>
>>> [XM]>>> Thank you. Except for this sentence in Section 2.1, there are
>>> still some sentences in Section 1 that seems confusing to me, e.g., it says
>>> "note that the IP encapsulation of OAM applies to those Virtual Network
>>> Identifiers (VNIs) that support the use of the necessary values of the
>>> Protocol Type field in the Geneve header". Could you please go through the
>>> whole document to make all the statements consistent? Some references
>>> to draft-ietf-nvo3-bfd-geneve and draft-xiao-nvo3-pm-geneve may be added to
>>> help the reader understand the difference between the Management VNI case
>>> and the really deployed VNI case.
>>>
>> GIM2>> Would the following edit of the text in Section 1 make the text
>> clear:
>> OLD TEXT:
>>    Also,
>>    note that the IP encapsulation of OAM applies to those Virtual
>>    Network Identifiers (VNIs) that support the use of the necessary
>>    values of the Protocol Type field in the Geneve header, i.e.,
>>    Ethertypes for IPv4 or IPv6.  It does not apply to VNIs that lack
>>    that support, e.g., VNIs that only support Ethernet Ethertypes.
>>    Analysis and definition of other types of OAM encapsulation in Geneve
>>    are outside the scope of this document.
>> NEW TEXT:
>>    The IP
>>    encapsulation of Geneve OAM defined in this document applies to an
>>    overlay service by way of introducing a Management Virtual
>>    Network Identifier (VNI) that could be used in combination with
>>    various values of the Protocol Type field in the Geneve header, i.e.,
>>    Ethertypes for IPv4 or IPv6.  Analysis and definition of other types
>>    of OAM encapsulation in Geneve are outside the scope of this
>>    document.
>>
>> [XM-2]>>> various values? It looks only two values, i.e., Ethertypes for
>> IPv4 or IPv6.
>>
>>
>> Could you highlight other cases that can benefit from a clarification?
>>
>> [XM-2]>>> In Section 2, it says
>>
>> "In the latter case, the test    packet MUST use the same Geneve encapsulation as the data packet    (except for the value in the Protocol Type field [RFC8926]),    including the value in the Virtual Network Identifier (VNI) field."
>> Why does it say "except for the value in the Protocol Type field [RFC8926]"? I don't think so.
>> In Section 2.1, it says "The ICMP echo reply is encapsulated in Geneve as specified in Section 2.2...", that's incorrect, do you mean Section 3?
>> In Section 2.2, it says "Active OAM in Geneve network uses an IP encapsulation", lacking the context of the Management VNI case.
>> In Section 2.2, it says "The UDP source port can be used to provide entropy...", I don't think so.
>> In Section 2.2, it says
>> "     Destination IP: IP address MUST NOT be of one of tenant's IP       addresses.  The IP address MUST be set to the loopback address       127.0.0.1/32 for IPv4, or the loopback address ::1/128 for IPv6       [RFC4291]."
>> Now that "the IP address MUST be set to the loopback address", why does it need to say "IP address MUST NOT be of one of tenant's IP addresses"?
>>
>>
>>> In section 1, the definition of VAP is introduced, and the only use of
>>>> it is within section 2.2, it says "Source IP: IP address of the originating
>>>> VAP".
>>>>
>>>> I'm a bit confused, to my understanding the VAP is irrelevant to the
>>>> test on Management VNI, the Source IP should be set to the IP address of
>>>> the originating NVE but not the originating VAP.
>>>>
>>> GIM>> Thank you for pointing that out to me. I removed the references to
>>> VAP in the document and updated the text accordingly.
>>>
>>> [XM]>>> Thanks.
>>>
>>>
>>> In section 2.1, it says "The Management VNI SHOULD be terminated on the
>>>> tenant-facing side of the Geneve encap/decap functionality, not the
>>>> DC-network-facing side (per definitions in Section 4 of [RFC8014]) so that
>>>> Geneve encap/decap functionality is included in its scope."
>>>>
>>>> I'm not sure this statement is accurate. The Management VNI is a
>>>> specific VNI not really deployed at the tenant-facing side, so it seems
>>>> impossible to be terminated on the tenent-facing side.
>>>>
>>> GIM>> You are right. The Management VNI is a logical construct and, as
>>> such, where it is terminated is also a logical entity. By pointing out
>>> where the termination of the Management VNI happens, the document provides
>>> useful information to an implementer. That information is important to
>>> ensure that Geneve encap/decap functionality is exercised by an active OAM.
>>>
>>> [XM]>>> OK.
>>>
>>>
>>> In section 1, it says "IP encapsulation conforms to these requirements
>>>> and is a suitable encapsulation of active OAM protocols in a Geneve overlay
>>>> network."
>>>>
>>>> I'm not sure this statement is comprehensive. For the first case
>>>> (Management VNI) discussed in section 2.1, I agree that IP encapsulation is
>>>> enough, but for the second case, Ethernet encapsulation is also needed,
>>>> which is clearly specified in draft-ietf-nvo3-bfd-geneve.
>>>>
>>> GIM>> I agree that the IP encapsulation using the Management VNI
>>> addresses the first of two scenarios analyzed in Section 2.1. But I don't
>>> think that it does not conform to the requirements listed in Section 2.
>>> Could you help me by identifying which of five requirements cannot be
>>> fulfilled by the IP encapsulation using the Management VNI?
>>>
>>> [XM]>>> REQ#1. As you indicated above, Management VNI is a logical
>>> construct, not the VNI really deployed at the NVE, and considering that the Ethernet
>>> over Geneve encap is the most popular one, I don't think a strict fate
>>> sharing can be fulfilled by the IP encapsulation using the Management VNI.
>>>
>> GIM2>> By using the Management VNI, in my opinion, we ensure the fate
>> sharing of an active Geneve OAM with Geneve overlay service. I agree that
>> the Management VNI may not be the most useful method to monitor an Ethernet
>> service over the Geneve tunnel. I think that is clear from the text of the
>> document.
>>
>> [XM-2]>>> OK, it's up to you. I reserve my suggestion to change the
>> quoted text.
>>
>>>
>>> In section 2.1, it says "The second case requires that a test packet be
>>>> transmitted using the VNI value for the traffic that is encountering
>>>> problems and the test packet is experiences network treatment as the
>>>> tenant's packets."
>>>>
>>>> I'm not sure this statement is accurate, "that is encountering
>>>> problems" seems applicable to ICMP Ping but not applicable to BFD, because
>>>> BFD itself is used to detect traffic problems.
>>>>
>>> GIM>> I think that the goal of BFD is well described in the Abstract of
>>> RFC 5880:
>>>    This document describes a protocol intended to detect faults in the
>>>    bidirectional path between two forwarding engines, including
>>>    interfaces, data link(s), and to the extent possible the forwarding
>>>    engines themselves, with potentially very low latency.
>>>
>>> From this definition I conclude that BFD detects faults, i.e., problems
>>> in the elements listed in the Abstract. Would you agree?
>>>
>>> [XM]>>> Let me elaborate a bit more. This sentence in Section 2.1
>>> implies that in the second case a test packet is transmitted only when the
>>> traffic is encountering problems, IMHO that's not the case, take BFD as an
>>> example, in the second case the BFD Control packets should be transmitted
>>> from the beginning, but not after detecting some traffic problems.
>>>
>> GIM2>>  Thank you for helping me to understand your concern. I hope I get
>> it now. Would the following update make the message unambiguous and
>> acceptable:
>> OLD TEXT:
>>    The second case requires that a test packet be transmitted using the
>>    VNI value for the traffic that is encountering problems and the test
>>    packet experiences network treatment as the tenant's packets.  Detail
>>    of that use case are outside the scope of this specification.
>> NEW TEXT:
>>
>> [XM-2]>>> I don't know what's wrong, but it seems your NEW TEXT
>> disappeared. The good thing is that I can see it from your attached Diff
>> file, and that's fine to me. At the same time, I propose to change the text
>> in Section 2.1 as below.
>>
>> OLD TEXT
>>
>>    In the first case, a communication problem between Network    Virtualization Edge (NVE) device A and NVE C was observed.  The    underlay, e.g., IP network, forwarding is working well but the Geneve    connection is unstable for all tenants of NVE A and NVE C.    Troubleshooting and localization of the problem can be done    irrespective of the VNI value.
>> NEW TEXT
>>    In the first case, a communication problem between Network    Virtualization Edge (NVE) device A and NVE C *exists*.  The    underlay, e.g., IP network, forwarding is working well but the Geneve    connection is unstable for all tenants of NVE A and NVE C.   *Detection,* troubleshooting and localization of the problem can be done    irrespective of the VNI value.
>>
>> Cheers,
>> Xiao Min
>>
>>
>>> Cheers,
>>>
>>> Xiao Min
>>>
>>>
>>> BTW, "the test packet is experiences network treatment" has nit.
>>>>
>>> GIM>> Thank you for catching it. Fixed.
>>>
>>>>
>>>> Best Regards,
>>>>
>>>> Xiao Min
>>>> Original
>>>> *From: *GregMirsky <[e-mail]>
>>>> *To: *肖敏10093570;
>>>> *Cc: *[e-mail] <[e-mail]>;[e-mail] <
>>>> [e-mail]>;[e-mail] <[e-mail]>;
>>>> [e-mail] <
>>>> [e-mail]>;
>>>> *Date: *2023年08月07日 06:12
>>>> *Subject: **Re: [nvo3] Working Group Last Call and IPR Poll for
>>>> draft-ietf-nvo3-geneve-oam-07*
>>>> _______________________________________________
>>>> nvo3 mailing list
>>>> [e-mail]
>>>> https://www.ietf.org/mailman/listinfo/nvo3
>>>>
>>>> Hi Xiao Min,
>>>> thank you for your suggestions. I've updated the draft to address your
>>>> concern. Please let me know if you agree with the changes highlighted in
>>>> the attached diff (the working version also includes updates that address
>>>> the editorial updates suggested by Donald Eastlake).
>>>>
>>>> Regards,
>>>> Greg
>>>>
>>>> On Tue, Jul 4, 2023 at 1:12 AM <[e-mail]> wrote:
>>>>
>>>>> Hi all,
>>>>>
>>>>>
>>>>> I support progressing this document to publication.
>>>>>
>>>>> At the same time, I strongly suggest the authors to rethink about the
>>>>> scope of this document.
>>>>>
>>>>> This document introduces two cases of using active OAM protocols for
>>>>> Geneve, the first case is to use the Management VNI, and the second case is
>>>>> to use the VNIs really deployed in the NVE, that's fine to me. However,
>>>>> it's said that the OAM encapsulation defined in Section 2.2 can be used for
>>>>> both cases, I don't think so. As specified in draft-ietf-nvo3-bfd-geneve,
>>>>> in order to use the VNIs really deployed, VAP based OAM solution is
>>>>> necessary, i.e., the MAC/IP address of VAP must be used as long as it's
>>>>> available, and then the VNI can be identified through VAP-to-VNI mapping.
>>>>> Besides, for the second case, both Ethernet over Geneve encap and IP over
>>>>> Geneve encap are needed. So with that said, the OAM encap defined in
>>>>> Section 2.2 can be slightly tweaked to be applicable to the first case
>>>>> only, and the OAM encap for the second case can be made outside the scope
>>>>> of this document.
>>>>>
>>>>>
>>>>> Best Regards,
>>>>>
>>>>> Xiao Min
>>>>> Original
>>>>> *From: *SamAldrin <[e-mail]>
>>>>> *To: *NVO3 <[e-mail]>;[e-mail] <[e-mail]
>>>>> >;[e-mail] <
>>>>> [e-mail]>;
>>>>> *Date: *2023年06月28日 14:27
>>>>> *Subject: **[nvo3] Working Group Last Call and IPR Poll for
>>>>> draft-ietf-nvo3-geneve-oam-07*
>>>>> _______________________________________________
>>>>> nvo3 mailing list
>>>>> [e-mail]
>>>>> https://www.ietf.org/mailman/listinfo/nvo3
>>>>>
>>>>> This email begins a two-week working group last call for
>>>>> draft-ietf-nvo3-geneve-oam-07
>>>>>
>>>>>  (https://datatracker.ietf.org/doc/draft-ietf-nvo3-geneve-oam/
>>>>> <https://datatracker.ietf.org/doc/draft-ietf-nvo3-bfd-geneve/>).
>>>>>
>>>>>
>>>>>
>>>>> Please review the draft and post any comments to the NVO3 working
>>>>> group list. If you have read the latest version of the draft but have no
>>>>> comments and believe it is ready for publication as an informational RFC,
>>>>> please also indicate so to the WG email list.
>>>>>
>>>>>
>>>>>
>>>>> We are also polling for knowledge of any undisclosed IPR that applies
>>>>> to this document, to ensure that IPR has been disclosed in compliance with
>>>>> IETF IPR rules (see RFCs 3979, 4879, 3669 and 5378 for more details).
>>>>>
>>>>> If you are listed as an Author or a Contributor of this document,
>>>>> please respond to this email and indicate whether or not you are aware of
>>>>> any relevant undisclosed IPR. The Document won't progress without answers
>>>>> from all the Authors and Contributors.
>>>>>
>>>>>
>>>>>
>>>>> Currently there are no IPR disclosures against this document.
>>>>>
>>>>>
>>>>>
>>>>> If you are not listed as an Author or a Contributor, then please
>>>>> explicitly respond only if you are aware of any IPR that has not yet been
>>>>> disclosed in conformance with IETF rules.
>>>>>
>>>>>
>>>>>
>>>>> This poll will run until Friday 12th July 2023.
>>>>>
>>>>>
>>>>>
>>>>> Regards
>>>>>
>>>>>
>>>>>
>>>>> Sam and Matthew
>>>>>
>>>>>
>>>>>
>>>>
>>>
>>
>