Re: [Tsv-art] Tsvart telechat review of draft-ietf-sfc-oam-framework-13
"Joel M. Halpern" <jmh@joelhalpern.com> Wed, 20 May 2020 18:17 UTC
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To: "Frank Brockners (fbrockne)" <fbrockne@cisco.com>, "Nagendra Kumar Nainar (naikumar)" <naikumar@cisco.com>, "tsv-art@ietf.org" <tsv-art@ietf.org>
Cc: "sfc@ietf.org" <sfc@ietf.org>, "last-call@ietf.org" <last-call@ietf.org>, "draft-ietf-sfc-oam-framework.all@ietf.org" <draft-ietf-sfc-oam-framework.all@ietf.org>
References: <158861910132.5213.12389985411421411727@ietfa.amsl.com> <B12ACAA0-BFBC-40D6-85D2-A7E056027C68@cisco.com> <BYAPR11MB2584D5A59E020682810099EFDAB60@BYAPR11MB2584.namprd11.prod.outlook.com> <e83de1dc-1f39-6281-7687-b6dd52567685@joelhalpern.com> <BYAPR11MB258403E216B7396323CD836EDAB60@BYAPR11MB2584.namprd11.prod.outlook.com>
From: "Joel M. Halpern" <jmh@joelhalpern.com>
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Subject: Re: [Tsv-art] Tsvart telechat review of draft-ietf-sfc-oam-framework-13
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So the question now is whether the text Murray suggested suffices for you? (We are still waiting to hear from Alvaro.) Yours, Joel On 5/20/2020 1:41 PM, Frank Brockners (fbrockne) wrote: > Thanks Joel. Per what I mentioned below, let's be clear that SF performance is out of scope for the doc. > And I think this was Alvaro's point as well. > > Cheers, Frank > >> -----Original Message----- >> From: Joel M. Halpern <jmh@joelhalpern.com> >> Sent: Mittwoch, 20. Mai 2020 19:21 >> To: Frank Brockners (fbrockne) <fbrockne@cisco.com>; Nagendra Kumar Nainar >> (naikumar) <naikumar@cisco.com>; tsv-art@ietf.org >> Cc: sfc@ietf.org; last-call@ietf.org; draft-ietf-sfc-oam-framework.all@ietf.org >> Subject: Re: Tsvart telechat review of draft-ietf-sfc-oam-framework-13 >> >> Frank, regarding your comment about SF performance, I thought the document >> was pretty clear that we consider that out of scope (c.f. the discussions with the >> various ADs.) >> >> If you can see a place to add text, please propose text. >> >> Thank you, >> Joel >> >> On 5/20/2020 1:10 PM, Frank Brockners (fbrockne) wrote: >>> Hi Nagendra, >>> >>> Thanks for the detailed reply. Please see inline (..FB). >>> >>>> -----Original Message----- >>>> From: Nagendra Kumar Nainar (naikumar) <naikumar@cisco.com> >>>> Sent: Samstag, 16. Mai 2020 16:16 >>>> To: Frank Brockners (fbrockne) <fbrockne@cisco.com>; tsv-art@ietf.org >>>> Cc: sfc@ietf.org; last-call@ietf.org; >>>> draft-ietf-sfc-oam-framework.all@ietf.org >>>> Subject: Re: Tsvart telechat review of >>>> draft-ietf-sfc-oam-framework-13 >>>> >>>> Hi Frank, >>>> >>>> Thank you for the review. Please see inline for the response.. >>>> >>>> >>>> Reviewer: Frank Brockners >>>> Review result: Ready with Nits >>>> >>>> This document has been reviewed as part of the transport area review >> team's >>>> ongoing effort to review key IETF documents. These comments were >> written >>>> primarily for the transport area directors, but are copied to the >> document's >>>> authors and WG to allow them to address any issues raised and >>>> also to the IETF >>>> discussion list for information. >>>> >>>> When done at the time of IETF Last Call, the authors should consider this >>>> review as part of the last-call comments they receive. Please always CC >>>> tsv-art@ietf.org if you reply to or forward this review. >>>> >>>> This document provides a reference framework for OAM for SFC. >>>> >>>> Comments: >>>> >>>> Section 3.1.1 SF availability: The text makes explicit reference to multiple >>>> instances of a SF. Consequently, it should be defined how availability of a >> SF >>>> is computed/determined in case multiple instances are deployed. >>>> >>>> <Nagendra> This is already clarified in the section as below: >>>> >>>> "For cases where >>>> multiple instances of an SF are used to realize a given SF for the >>>> purpose of load sharing, SF availability can be performed by checking >>>> the availability of any one of those instances, or the availability >>>> check may be targeted at a specific instance." >>>> >>>> This further >>>> leads to the question, whether availability is always a "binary" state >>>> (available / not-available), or could a SF be e.g. 99% available? >>>> >>>> <Nagendra>The availability is measured as binary state. I am not sure >>>> what is 99% available. If it means getting 99 responses for 100 >>>> probes sent, I think it falls under packet loss category which in turn is >> performance measurement. >>> >>> ...FB: Thanks. Though I'm still not entirely following. If availability is binary and >> I put the statements above together, what would be the availability of the >> following setup: There is an SF that is made up of 100 instances. 99 of these >> instances are powered down entirely. And the 1 instance that is "up" is >> alternating between servicing requests for 10min followed by not servicing >> requests for 10min. Would the SF be considered "available"? >>> >>>> >>>> Section 3.1.2 >>>> SF performance: What is the impact of a "multiple instance SF >>>> deployment" on SF >>>> performance measurement? >>>> >>>> <Nagendra>I think we covered this in SF availability but not here. >>>> Does the below updated text look better? >>>> >>>> OLD: >>>> On the one hand, the performance of any specific SF can be quantified >>>> by measuring the loss and delay metrics of the traffic from SFF to >>>> the respective SF, while on the other hand, the performance can be >>>> measured by leveraging the loss and delay metrics from the respective >>>> SFs. The latter requires SF involvement to perform the measurement >>>> while the former does not. >>>> >>>> NEW: >>>> On the one hand, the performance of any specific SF can be quantified >>>> by measuring the loss and delay metrics of the traffic from SFF to >>>> the respective SF, while on the other hand, the performance can be >>>> measured by leveraging the loss and delay metrics from the respective >>>> SFs. The latter requires SF involvement to perform the measurement >>>> while the former does not. For cases where >>>> multiple instances of an SF are used to realize a given SF for the >>>> purpose of load sharing, SF performance can be quantified by measuring >>>> the metrics for any one instance of SF or by measuring the metrics for >>>> a specific instance. >>>> >>>> The section only talks about loss and delay as >>>> performance criteria. It would be good to state that other >>>> performance criteria >>>> (e.g. specific to the SF, throughput, etc.) exist. >>>> >>>> <Nagendra> We can add the below to Section 3.1.2: >>>> >>>> NEW: >>>> "The metrics measured to quantify the performance of the SF component >>>> is not just limited to loss and delay. Other metrics such as >>>> throughout also exist and the choice of metrics for performance >>>> measurement is outside the scope of this document." >>>> >>>> Section 3.2.1 SFC >>>> availability: The current definition is very focused on connectivity >>>> verification, i.e. it tries to answer the question: "Does my SFC transport >>>> packets?". IMHO we should also ask the question "Does my SFC process >> the >>>> packets correctly?" - because if packets are not processed per the SFC >>>> definition, we might not call the SFC available. >>>> >>>> <Nagendra> I think this is already handled by SF availability. The >>>> end-to-end SFC availability is verified by steering the OAM packet >>>> over the ordered set of SFs within the SFC. This is more like daisy >>>> chaining the availability of SFs within the SFC to determine >>>> end-to-end SFC availability. If the derived solution verifies the SF >>>> availability not just based on the uptime but based on the service >>>> treatment, it also answers the question "Does my SFC process the packets >> correctly". Let us know if there is any further clarity required. >>>> >>>> While 3.2.2 states that "any >>>> SFC-aware network device should have the ability to make performance >>>> measurements" a similar statement isn't found in 3.2.1. IMHO the ability >> for >>>> availability checks is probably a prerequisite for performance >> measurement. >>>> >>>> <Nagendra> The ability to perform end-to-end or partial SFC >>>> availability verification is already mentioned in section 3.2.1 as below: >>>> >>>> " In order to perform service connectivity verification of an SFC/SFP, >>>> the OAM functions could be initiated from any SFC-aware network >>>> devices of an SFC-enabled domain for end-to-end paths, or partial >>>> paths terminating on a specific SF, within the SFC/SFP" >>>> >>>> Please let us know if you have any suggestion to improve if there is >>>> a lack of clarity. >>>> >>>> Section 3.2.2 SFC performance measurement: The section only >>>> mentions the need >>>> for performance measurement. It misses the definition of what >>>> SFC performance >>>> measurement is. >>>> >>>> <Nagendra> >>> >>> ...FB: Thanks for the suggested updates, which would definitively improve the >> text. One problem about SFC performance remains though IMHO. >>> All the text so far is focused on the connectivity within a SFC - not the service >> itself. I.e. If you'd consider a "laundry service" - we focus a lot on how long it >> takes to get the clothes shipped to and from the washing machine, but we don't >> focus on how well the washing machine washes the clothes. >>> IMHO we should either expand on the performance of the SFC and SF wrt/ the >> service (especially given that you define a service layer in section 2) - or clearly >> state that the framework would just focus on connectivity between SFs. >>> >>> >>>> >>>> Section 3.3. Classifier component: The section mentions the >>>> need for the ability to perform performance measurement of the classifier >>>> component. What is performance measurement of the classifier? What >> does >>>> performance measurement of the classifier component comprise? >>>> >>>> <Nagendra>We can add the below text: >>>> >>>> OLD: >>>> Any SFC-aware network device should have the ability to perform >>>> performance measurement of the classifier component for each SFC. >>>> >>>> NEW: >>>> Any SFC-aware network device should have the ability to perform >>>> performance measurement of the classifier component for each SFC. >>>> The performance can be quantified by measuring the performance >>>> metrics of the >>>> traffic from the classifier for each SFC/SFP. >>>> >>>> Section 3.4. / >>>> 3.5. Availability/PM of the underlay and overlay network: It would be good >> to >>>> add a sentence that states that the mechanisms for availability/PM which >> are >>>> offered by the technologies used by the overlay/underlay are >>>> used, rather than >>>> new methods specifically for SFC would be defined. >>>> >>>> <Nagendra>Yes, that makes sense. Please check the below text: >>>> >>>> OLD: >>>> Any SFC-aware network device may have the ability to perform >>>> availability check or performance measurement of the overlay network. >>>> >>>> NEW: >>>> Any SFC-aware network device may have the ability to perform >>>> availability check or performance measurement of the overlay network. >> Any >>>> existing OAM tools and techniques can be leveraged for this purpose. >>>> >>>> Section 4. SFC OAM >>>> Functions: It would be good, if examples in section 4 could also include >> more >>>> "recent" methods such as OWAMP/TWAMP (RFC4656, RFC 5357). >>>> >>>> <Nagendra> >>>> >>>> OLD: >>>> Delay within an SFC could be measured based on the time it takes for >>>> a packet to traverse the SFC from the ingress SFC node to the egress >>>> SFF. As SFCs are unidirectional in nature, measurement of one-way >>>> delay [RFC7679] is important. In order to measure one-way delay, >>>> time synchronization MUST be supported by means such as NTP, PTP, >>>> GPS, etc. >>>> >>>> NEW: >>>> Delay within an SFC could be measured based on the time it takes for >>>> a packet to traverse the SFC from the ingress SFC node to the egress >>>> SFF. Measurement protocols such as One-way Active Measurement >>>> Protocol (OWAMP) [RFC4656], Two-way Active Measurement Protocol >>>> (TWAMP) [RFC5357] can be used to measure the characteristics. As >>>> SFCs are unidirectional in nature, measurement of one-way >>>> delay [RFC7679] is important. In order to measure one-way delay, >>>> time synchronization MUST be supported by means such as NTP, >>>> Precision Time Protocol (PTP), >>>> GPS, etc. >>>> >>>> Section 4.4. >>>> Performance Measurement: Focus is entirely on the PM of the >> connectivity, >>>> rather than on the SF. How about covering PM for the SF as well? >>>> >>>> <Nagendra> I am not sure I understand what is missing. Do you have >>>> any suggestion for the text improvement?. >>> >>> ...FB: See above. This would be about adding a capability to assess how well >> the washing machine washes my laundry. >>> >>>> >>>> Section 5.1 >>>> OAM Tool Gap Analysis: >>>> - Not sure what "NVo3 OAM" refers to. Could that be explained >>>> below the table >>>> and in section 1.2.1? >>>> >>>> <Nagendra> Combining this with other below queries as they appears to >>>> be related. >>>> >>>> - E-OAM needs to be detailed. Is seems that CFM >>>> (802.1ag) and not 802.3ah is refered to here. >>>> >>>> <Nagendra> Per my understanding, 802.ah is 1-hop while 802.3ag can be >>>> more than 1 hop and both uses Ethernet frames. So I think both are >> applicable here. >>>> My response regarding E-OAM details in this section is combined below. >>> >>> ...FB: Maybe I missed it - but I don't see text that refers to CFM or EFM OAM. >> Where is this covered? IMHO we would need references to IEEE standards to >> avoid confusion. >>> >>>> >>>> - "Trace" in the "Trace" column >>>> need to be extended on. Is this traceroute? Paris-Traceroute? >>>> IOAM- Loopback? >>>> >>>> IPPM needs to be detailed, because IPPM is not a tool as such >>>> but an IETF WG. >>>> Does this refer to OWAMP/TWAMP/etc. as defined by IPPM? >>>> >>>> <Nagendra> Combining the above queries. >>>> >>>> OLD: >>>> There are various OAM tool sets available to perform OAM functions >>>> within various layers. These OAM functions may be used to validate >>>> some of the underlay and overlay networks. Tools like ping and trace >>>> are in existence to perform connectivity check and tracing of >>>> intermediate hops in a network. These tools support different >>>> network types like IP, MPLS, TRILL, etc. There is also an effort to >>>> extend the tool set to provide connectivity and continuity checks >>>> within overlay networks. BFD is another tool which helps in >>>> detecting data forwarding failures. Table 3 below is not >>>> exhaustive >>>> >>>> NEW: >>>> There are various OAM tool sets available to perform OAM functions >>>> within various layers. These OAM functions may be used to validate >>>> some of the underlay and overlay networks. Tools like ping and trace >>>> are used to perform connectivity check and tracing of >>>> intermediate hops in a network. These tools are already available for >>>> different types of networks such as IP, MPLS, TRILL, etc. >>>> >>>> E-OAM offers OAM mechanisms such as an Ethernet continuity check for >>>> Ethernet links. There is an effort around NVO3 OAM to provide >>>> connectivity and continuity checks for networks that use NVO3. BFD >>>> is used for the detection of data plane forwarding failures. >>> >>> ...FB: Check whether NVO3 WG will indeed deliver a solution and "NVO3 OAM" >> indeed existis. If in doubt, it might be better to avoid forward looking >> references. Per my note above, it would be good to explicitly refer to IEEE >> standards as opposed to introducing a new term like "E-OAM". >>> >>>> >>>> The IPPM framework [RFC 2330] offers tools such as OWAMP [RFC4656] >>>> and TWAMP [RFC5357] (collectively referred as IPPM in this section) >>>> to measure various performance metrics. MPLS Packet Loss Measurement >>>> (LM) and Packet Delay Measurement (DM) (collectively referred as >>>> MPLS_PM in this section) [RFC6374] offers the ability to measure >> performance metrics in MPLS network. >>>> >>>> Table 3 below is not exhaustive. >>>> >>>> Section 6.4.3 IOAM: >>>> - The section states that IOAM "may be used to perform various SFC OAM >>>> functions as well". It would be good to expand on this statement: E.g. >> IOAM >>>> Trace-Option Type could be leveraged for SFC tracing. IOAM >>>> Direct-Export Option >>>> Type could be leveraged. - How would we deal with the IOAM Active Flag >>>> (draft-ietf-ippm-ioam-flags-01) when used with SFC OAM? >>>> >>>> <Nagendra> The intention of the section is to highlight the >>>> applicability of different OAM toolsets for OAM functions at service >>>> layer. I am not sure if we really should try explaining all the >>>> possible options within each tool. But I agree that it is worth >>>> clarifying the availability of IOAM options for tracing. think we can >>>> clarify that different IOAM Option-Types are available for OAM functions >> such as SFC tracing. Can you check if the below looks ok? >>>> >>>> OLD: >>>> [I-D.ietf-sfc-ioam-nsh] defines how In-Situ OAM data fields are >>>> transported using NSH header. [I-D.ietf-sfc-proof-of-transit] >>>> defines a mechanism to perform proof of transit to securely verify if >>>> a packet traversed the relevant SFP or SFC. While the mechanism is >>>> defined inband (i.e., it will be included in data packets), it may be >>>> used to perform various SFC OAM functions as well. >>>> >>>> NEW: >>>> [I-D.ietf-sfc-ioam-nsh] defines how In-Situ OAM data fields are >>>> transported using NSH header. [I-D.ietf-sfc-proof-of-transit] >>>> defines a mechanism to perform proof of transit to securely verify if >>>> a packet traversed the relevant SFP or SFC. While the mechanism is >>>> defined inband (i.e., it will be included in data packets), IOAM Option-Types >>>> such as IOAM Trace Option-Types can also be used to perform other >>>> SFC OAM function >>>> such as SFC tracing. >>>> >>>> - The text states >>>> "In-Situ OAM could be used with O bit set": Why would IOAM be used with >> the >>>> overflow bit set for SFC OAM? For details on IOAM's O-bit, see section >> 4.4.1 in >>>> https://tools.ietf.org/html/draft-ietf-ippm-ioam-data-09. >>>> >>>> <Nagendra> The O bit referred here is not the O bit in IOAM but the >>>> one in NSH/Overlay header. To avoid any confusion, this can be updated as >> below: >>>> >>>> OLD: >>>> In-Situ OAM could be used with O bit set to perform SF availability >>>> and SFC availability or performance measurement. >>>> >>>> NEW: >>>> In-Situ OAM could be used with O bit in the overlay header set, to >>>> perform SF availability >>>> and SFC availability or performance measurement. >>> >>> ... FB: Ah, ok. Given that this section is about IOAM and not NSH, I'd rather >> explicitly refer to NSH here. E.g. If SFC is realized using NSH, then the O-bit in the >> NSH header could be used to indicated OAM traffic. You could refer to >> https://tools.ietf.org/html/draft-ietf-sfc-ioam-nsh-03#section-4.2 explicitly. >>> >>>> >>>> Section 6.4.4 SFC >>>> Traceroute: - This section refers to an expired draft (even calling out the >>>> fact that the draft has exipred), but also mentions that functionality is >>>> available and implemented in OpenDaylight. Consider removing the >>>> references to >>>> the expired draft and rather add references to OpenDaylight >>>> documents. - IOAM >>>> Loopback (see draft-ietf-ippm-ioam-flags-01) could apply SFC >>>> Traceroute as well. >>>> >>>> <Nagendra>Ok. Let me check if I can find some reference for ODL. >>>> >>>> Detailed set of nits that I encountered while reading through >>>> the document ([x] >>>> references line number x) – hope that they are helpful in further improving >> the >>>> doc: >>>> >>>> <Nagendra> Yes of course (. >>>> >>>> [global] s/an SF/a SF/ -- and similarly SFC/SFF >>>> >>>> <Nagendra>Other RFCs uses "an SF/SFF". So the draft is updated >>>> accordingly. If your suggestion is to substitute "a SF" to "an SF", it is done (. >>>> >>>> [176] "OAM Controller" not defined >>>> >>>> <Nagendra>We can change it as below: >>>> >>>> OLD: >>>> OAM controllers are assumed to be within the same administrative >>>> domain as the target SFC enabled domain. >>>> >>>> NEW: >>>> OAM controllers are SFC-aware network devices that are capable of >>>> generating OAM packets. They are assumed to be within the same >>>> administrative domain as the target SFC enabled domain. >>>> >>>> [202] Why just Virtual Machines and no containers? Suggest to make >> things >>>> generic and talk about virtual and physical entities. >>>> >>>> <Nagendra> We changed this as virtual entities. >>>> >>>> This comment applies throughout the document. >>>> [216] Ethernet OAM: Add reference. Do you refer to physical >>>> layer Ethernet OAM >>>> (802.3ah) or CFM (802.1ag)? >>>> >>>> <Nagendra> The response was provided in the above comment section. >>>> >>>> [243] s/uses the overlay network/uses the overlay >>>> network layer/ >>>> >>>> <Nagendra> Done. >>>> >>>> [246] Could we add a few examples of "various overlay network >>>> technologies"? For the underlay network layer several examples are listed. >>>> >>>> <Nagendra> Ok. >>>> >>>> [248] What does "mostly transparent" mean? >>>> >>>> <Nagendra> The data plane elements connecting the overlay layer nodes >>>> may not always process the overlay header. >>> >>> ...FB: How about we explain this in the document? >>> >>>> >>>> [254] What does "tight coupling" >>>> between the link layer and the physical technology mean? >>>> >>>> <Nagendra>I am not sure I understand the nit here. Do you see any >>>> difficulty in parsing the sentence? >>> >>> ...FB: Not sure what "tight coupling" means here. Could you clarify what is >> "tight coupling" vs. "not tight coupling"? >>> >>>> >>>> [255] Suggest to avoid >>>> terms like "popular" - popularity can change, standards stay >>>> >>>> <Nagendra> Ok. This is changed as "Ethernet is one such choice..." >>>> >>>> [256] Acronyms >>>> "POS" and "DWDM" are not defined >>>> >>>> <Nagendra> Added. >>>> >>>> [274] Link start/end-points don't seem to >>>> always align with the underlay network in the diagram >>>> >>>> <Nagendra> Fixed it. >>>> >>>> [287] s/may comprise >>>> of/may consist of/ >>>> >>>> <Nagendra>We fixed it as "may comprise".. >>>> >>>> [288] s/but not shown/but is not shown/ >>>> >>>> <Nagendra> We fixed this as "intermediate nodes not shown...: >>>> >>>> [307] >>>> s/devices/device/ >>>> >>>> <Nagendra> Done. >>>> >>>> [308] What is a "controller"? >>>> >>>> <Nagendra> We discussed this in the above comment section. >>>> >>>> [314] s/includes/include/ >>>> >>>> <Nagendra>Done. >>>> >>>> [319] >>>> Add hSFC to list of acronyms in section 1.2.1 >>>> >>>> <Nagendra> This is expanded in the respective section. We added it in >>>> the acronym section as well. >>>> >>>> [320] Add IBN to list of acronyms >>>> in section 1.2.1 >>>> >>>> <Nagendra> Ok, Done. >>>> >>>> [325] s/includes/include/ >>>> >>>> <Nagendra> Done. >>>> [359] The function/term "controller" >>>> requires definition. >>>> >>>> <Nagendra> Done, as mentioned in the above comment section. >>>> >>>> [383] s/?./?/ >>>> >>>> [398] s/get the got/got/ >>>> >>>> <Nagendra> Done. >>>> >>>> [461] >>>> s/devices/device/ >>>> >>>> <Nagendra> Done. >>>> >>>> [469] Does it have to be equal cost multipath at the service >>>> layer, or could unequal cost multipath also be an option for load- >> balancing? >>>> >>>> <Nagendra>I didn’t see any discussion specific to ECMP/UCMP in the >>>> architecture RFC. >>> >>> ...FB: Hmm. I did not see that RFC7665 is only about equal cost multipath. >>>> >>>> [521] Not sure whether the overlay network establishes the service plane. >> Isn't >>>> it that the overlay network establishes connectivity for the SFC-related >>>> functions in the service plane? >>>> >>>> <Nagendra> The service layer is established over the overlay network >>>> layer. I am not sure if it is right to say overlay network provides >>>> connectivity for service layer (. >>> >>> ...FB: Overlay network is one component of the service layer, isn't it. So it is >> required but not sufficient. >>> >>>> >>>> [531] s/components/component/ [545] remove >>>> "underlay" >>>> >>>> <Nagendra> Done. >>>> >>>> [595] s/devices/device/ >>>> >>>> <Nagendra> Done. >>>> >>>> [600] s/action/an action/ >>>> >>>> <Nagendra> Done. >>>> >>>> [601] Expand on >>>> "TTL or other means" (TTL also needs to be added to acronyms in 1.2.1). Is >> this >>>> specific to NSH? Or specific to IPv4? >>>> >>>> <Nagendra> TTL is listed as well-known abbrev in https://www.rfc- >>>> editor.org/materials/abbrev.expansion.txt and so we left it as it is. >>>> TTL in this document refers to NSH TTL field. >>> >>> ...FB: Let's ensure we refer to NSH TTL in this case. Given that SFC can be done >> with other means than NSH, implicit reference to NSH might be a problem. >>>> >>>> [630] Mention that for "approximation of >>>> packet loss for a given SFC can be derived" to be applicable, SFC OAM >> packets >>>> would need to be forwarded the same as live user traffic. >>>> >>>> <Nagendra> As it is intending to derive the approximate loss value, I >>>> am not sure if we need this additional consideration that the OAM >>>> packet would need to follow the live user traffic. Let me know if you think >> otherwise. >>> >>> ...FB: IMHO we should - given that it is one potential complication. >>> >>>> >>>> [636] Is uppercase >>>> "MUST" applicable to an informational document? Especially given that >>>> RFC2119/RFC8174 is explicitly referenced by the draft. >>>> >>>> <Nagendra> Based on various reviewer comments, we removed the use of >>>> any normative statement. >>>> >>>> [666] Add MPLS, TRILL to >>>> acronyms in 1.2.1 >>>> >>>> <Nagendra> Ok. Done. >>>> >>>> [678] s/exhaustive/exhaustive./ >>>> >>>> <Nagendra> Done. >>>> >>>> [720] Is uppercase "SHOULD" applicable to an informational document? >>>> Especially given that RFC2119/RFC8174 is explicitly referenced by the >> draft. >>>> >>>> <Nagendra> Based on various reviewer comments, we removed the use of >>>> any normative statement. >>>> >>>> [722] Is uppercase "MAY" applicable to an informational document? >> Especially >>>> given that RFC2119/RFC8174 is explicitly referenced by the draft. >>>> >>>> <Nagendra> Based on various reviewer comments, we removed the use of >>>> any normative statement. >>>> >>>> [754] >>>> s/packet/packets/ >>>> >>>> [755] s/to next node/to the next node/ >>>> >>>> [771] How does this >>>> requirement align with the earlier paragraph, e.g. in case a >>>> node sends an ICMP >>>> reply? It would probably make sense to scope the statement to e.g. NSH. >>>> >>>> <Nagendra> As mentioned in the statement, the node that initiates the >>>> OAM packet must set the marker and so this statement is applicable >>>> for the initiating node. >>>> >>>> [806] >>>> s/function/functions/ >>>> >>>> <Nagendra> Done >>>> >>>> [809] s/from relevant node/from the relevant node/ >>>> >>>> <Nagendra> Done >>>> >>>> [810] >>>> s/generate ICMP/generate an ICMP/ >>>> >>>> <Nagendra> Done >>>> >>>> [812] s/from last/from the last/ >>>> >>>> <Nagendra> Done >>>> >>>> [830] >>>> s/perform continuity/perform the continuity/ >>>> >>>> <Nagendra> Done >>>> >>>> [834] s/with relevant/with the >>>> relevant >>>> >>>> <Nagendra> Done >>>> >>>> [835] s/perform partial SFC availability./perform a partial SFC >>>> availability check./ >>>> >>>> <Nagendra> Done >>>> >>>> [851] For "In-Situ OAM data fields" add a normative >>>> reference to draft-ietf-ippm-ioam-data >>>> >>>> [905] Add "CLI" to section 1.2.1 >>>> acronyms >>>> >>>> <Nagendra> Done >>>> >>>> [920] Add a reference for NETCONF ->RFC6241 >>>> >>>> <Nagendra> Done >>>> >>>> Once again, thanks a lot for the great comments. >>>> >>>> Regards, >>>> Nagendra >>> >>> Thanks again for considering the comments in great detail. Much appreciated. >>> >>> Cheers, Frank >>>> >>>> >>>> >>>
- [Tsv-art] Tsvart telechat review of draft-ietf-sf… Frank Brockners via Datatracker
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Nagendra Kumar Nainar (naikumar)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Frank Brockners (fbrockne)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Joel M. Halpern
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Carlos Pignataro (cpignata)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Frank Brockners (fbrockne)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Joel M. Halpern
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Nagendra Kumar Nainar (naikumar)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Frank Brockners (fbrockne)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Frank Brockners (fbrockne)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Joel M. Halpern
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Frank Brockners (fbrockne)
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Joel Halpern Direct
- Re: [Tsv-art] Tsvart telechat review of draft-iet… Nagendra Kumar Nainar (naikumar)