Hi Tom, A quick top-post response: I believe you are making assumptions about how this works in a multiplayer environment, and about which nodes can modify what.
Instead of email, let us (like Frank had also said) expand on a tighter description and use case example in the draft itself, Section 3, and close this loop that way. Thumb typed by Carlos Pignataro. Excuze typofraphicak errows > On Apr 22, 2018, at 11:28, Tom Herbert <[email protected]> wrote: > > On Sun, Apr 22, 2018 at 2:21 AM, Carlos Pignataro (cpignata) > <[email protected]> wrote: >> Hi Tom, >> >> I agree that using IOAM in IPv6 both e2e and hbh is a powerful and useful >> combo! >> >> My point, sorry if I was not clear, is that an “SFC Hop” does not correspond >> to a transport encapsulation hop, and that IOAM can be in-situ’ed to the >> encapsulation that realizes the (service, overlay, otherwise higher) >> topology (which can be IPv6 natively or something else as well) >> > Carlos, > > AFACT, the intent is that nodes along the path of a packet containing > in-situ ippm data may modify the ippm data as described in > draft-ietf-ippm-ioam-data. Your comment confirms my belief that part > of the intent is that intermediate nodes, specifically nodes that are > not addressed by the destination address of a packet, may also modify > ippm data. > > If this is correct, then I understand how this process could work > correctly with hop-by-hop options. However, I don't understand how > this can work correclty with encapsulation where the ippm data is > within the encapsulation. IP has no allowance for intermediate nodes > to modify transport payloads. For example, if UDP payloads are being > modified in the network, then this introduces the possibility of > silent corruption when the port number is misinterpreted. > > Thanks, > Tom > > >> Thanks, >> >> Thumb typed by Carlos Pignataro. >> Excuze typofraphicak errows >> >>> On Apr 21, 2018, at 11:05, Tom Herbert <[email protected]> wrote: >>> >>> On Fri, Apr 20, 2018 at 12:03 PM, Carlos Pignataro (cpignata) >>> <[email protected]> wrote: >>>> Tom, >>>> >>>> On Apr 17, 2018, at 10:22 AM, Tom Herbert <[email protected]> wrote: >>>> >>>> On Tue, Apr 17, 2018 at 12:51 AM, Frank Brockners (fbrockne) >>>> <[email protected]> wrote: >>>> >>>> >>>> Hi Tianran, >>>> >>>> Tom's note already includes the hint: You'll add IOAM data to the >>>> protocol/layer that you're interested in monitoring. Again using Geneve >>>> over >>>> IPv6 as an example: >>>> * If you're interested in the overlay, i.e. Geneve (e.g. timestamping the >>>> packet when it enters and exists the tunnel) - you'd add IOAM data to >>>> Geneve >>>> * If you're interested in the underlay, i.e. IPv6 (e.g. you'd like to >>>> understand which path packets take in the v6 network) - you'd add IOAM data >>>> to IPv6 >>>> * If you're interested in both, then you'd add IOAM data to Geneve and IPv6 >>>> >>>> Frank, >>>> >>>> In that case why not just use a hop-by-hop option for measuring the >>>> underlay and a destination option for measuring the overlay? The >>>> advantage is that this works _any_ IP encapsulation method or any IP >>>> protocol for that matter. >>>> >>>> >>>> Because you want to instrument the layer that you want to measure. >>>> Because there’s cases with more unnatural layering where there’s a desire >>>> to >>>> correlate and compare measurements across layers (in a way in which, for >>>> example, the Service layer is tested in a service chaining scenario, not >>>> the >>>> IPv6 hop-by-hop. >>>> Because different topologies expose different Hops and IPv6 HBH goes by the >>>> IPv6 node topology. >>>> Because not everything is IPv6, and because you have cases of IPv6 over >>>> something as well. >>>> Those are quick ones that come to mind. >>>> >>> Carlos, >>> >>> Please see my other email that details some use cases that shows >>> destination options are functionally equivalent to ippm in >>> encapsulation, and also my comments that the IPv6 has superior >>> capabilities to cover in-situ ippm requirements (in particular that IP >>> options are the _only_ protocol conformant means for intermediate >>> nodes to change IP payloads needed for IOAM tracing). >>> >>> I don't have a general issue with supporting ippm in encapsulation, >>> but I do think this should be viewed as legacy support. Note there is >>> no concept of segment routing in IPv4, they are blazing forward only >>> on IPv6 so it is reasonable to take this view. Personally, I don't >>> think this is a disadvantage to SR. IPv6 does have more capabilities >>> than IPv4 and we're now seeing protocols that will take advantage of >>> those. Features like this are good motivation for moving to IPv6, >>> which in the long run is good for the Internet! >>> >>> Tom >>> >>>> Frank, >>>> I don't believe adding ippm to every >>>> encapsulation protocol is straightforward: e.g. >>>> draft-brockners-ippm-ioam-geneve describe but notes the limited size >>>> of header, draft-weis-ippm-ioam-gre states that a new EtherType would >>>> be needed just for this purpose. This also entails additional >>>> encapsulation-specific HW support also, whereas support destination >>>> and hbh options could be more generic. >>>> >>>> >>>> Engineering is about trade-offs. If you want to measure Geneve, there are >>>> limitations. But instead of trying to prove why it does not work, I’ll >>>> point >>>> to working demos of where it does — many of which on different HW/SW and >>>> encaps, shown at various IETF events. >>>> >>>> Thanks, >>>> >>>> — Carlos Pignataro >>>> >>>> Tom >>>> >>>> Draft draft-ietf-ippm-ioam-data-02 already mentions layering (see section >>>> 3): >>>> "Layering: If several encapsulation protocols (e.g., in case of tunneling) >>>> are stacked on top of each other, IOAM data-records could be present at >>>> every layer. The behavior follows the ships-in-the-night model." >>>> >>>> Given the discussion here, we'll add some additional text in the next >>>> revision to make things crisper (e.g. adding an example might help). >>>> >>>> Frank >>>> >>>> -----Original Message----- >>>> From: Tianran Zhou <[email protected]> >>>> Sent: Dienstag, 17. April 2018 03:18 >>>> To: Tom Herbert <[email protected]> >>>> Cc: Shwetha Bhandari (shwethab) <[email protected]>; Frank Brockners >>>> (fbrockne) <[email protected]>; Mickey Spiegel >>>> <[email protected]>; NVO3 <[email protected]>; Service Function >>>> Chaining IETF list <[email protected]>; IETF IPPM WG <[email protected]> >>>> Subject: RE: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> >>>> I think it's better that Frank or Shwetha can explain the multi-layer use >>>> case in detail. >>>> >>>> Tianran >>>> >>>> -----Original Message----- >>>> From: Tom Herbert [mailto:[email protected]] >>>> Sent: Monday, April 16, 2018 10:40 PM >>>> To: Tianran Zhou <[email protected]> >>>> Cc: Shwetha Bhandari (shwethab) <[email protected]>; Frank Brockners >>>> (fbrockne) <[email protected]>; Mickey Spiegel >>>> <[email protected]>; NVO3 <[email protected]>; int-area >>>> <[email protected]>; Service Function Chaining IETF list >>>> <[email protected]>; IETF IPPM WG <[email protected]> >>>> Subject: Re: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> >>>> On Mon, Apr 16, 2018 at 6:31 AM, Tianran Zhou <[email protected]> >>>> wrote: >>>> >>>> Hi Shwetha, >>>> >>>> You are talking about the outer encapsution. It is straight forward >>>> for the underlay to record by the header. But what about the >>>> overlay, i.e., inner encapsulation(e.g. geneve)? Without special >>>> configuration, intermediate node will not read the inner header, >>>> hence not be able to process IOAM.e >>>> >>>> >>>> Hi Tianran, >>>> >>>> I believe that is also not protocol conformant. Intermediate nodes >>>> should not be processing transport layer data as this can lead to >>>> misinterpretation and possibly silent data corruption. >>>> >>>> For instance, Geneve is a UDP encapsulation protocol with assigned port >>>> 6081. >>>> In order for an intermediate device to process the Geneve >>>> encapsulation header it would need to look for packets with >>>> destination port of 6081 since that is the only possible >>>> discriminator. However, transport port numbers do not have global >>>> meaning and hosts may use port numbers for other purposes (RFC7605 >>>> describes this). So a packet to port 6081 might be something other >>>> than Geneve and may be misinterpreted. If a misinterpreted packet is >>>> changed >>>> (like ippm data is written) then that would be systematic silent data >>>> corruption. >>>> >>>> As far as I know, hop-by-hop options is the only protocol confirming >>>> mechanism that allows an intermediate note to change data of packet in >>>> flight. >>>> Encpasulation is the only conforming mechanism that allows an >>>> intermediate node to add data (like extension headers) to a packet in >>>> flight. >>>> >>>> Tom >>>> >>>> Maybe we are not synced by this overlay/underlay use case. :-) >>>> >>>> Tianran >>>> >>>> >>>> >>>> ________________________________ >>>> Sent from WeLink >>>> >>>> 发件人： Shwetha Bhandari (shwethab) >>>> 收件人： Tianran Zhou<[email protected]>;Frank Brockners >>>> (fbrockne)<[email protected]>;Mickey >>>> Spiegel<[email protected]>;Tom >>>> Herbert<[email protected]> >>>> 抄送： NVO3<[email protected]>;int-area<[email protected]>;Service Function >>>> Chaining IETF list<[email protected]>;IETF IPPM WG<[email protected]> >>>> 主题： Re: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> 时间： 2018-04-16 18:17:01 >>>> >>>> Hi Tianran, >>>> >>>> If I recall right, it is not written in the ioam data draft. >>>> >>>> >>>> Data draft is defining the data to be carried in IOAM in an >>>> encapsulation agnostic way, it does not specify how the >>>> encapsulation protocol is configured. >>>> >>>> >>>> >>>> Yes, node by node configuration is an easy way. >>>> >>>> >>>> While it is, it does not have to be a node by node configuration. It >>>> can be part of the encapsulation definition. >>>> >>>> For e.g. If the encapsulation is IPv6 and if we define the data to >>>> be carried as HbH options, then based on the Option Type with >>>> highest order 2 bits set to 00 then the v6 nodes that implement IOAM >>>> will process the option and others will skip over. >>>> >>>> >>>> >>>> >>>> >>>> Thanks, >>>> >>>> Shwetha >>>> >>>> >>>> >>>> From: ippm <[email protected]> on behalf of Tianran Zhou >>>> <[email protected]> >>>> Date: Monday, April 16, 2018 at 2:36 PM >>>> To: "Frank Brockners (fbrockne)" <[email protected]>, Mickey >>>> Spiegel <[email protected]>, Tom Herbert >>>> <[email protected]> >>>> Cc: NVO3 <[email protected]>, "[email protected]" <[email protected]>, >>>> Service Function Chaining IETF list <[email protected]>, IETF IPPM WG >>>> <[email protected]> >>>> Subject: Re: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> >>>> >>>> >>>> Hi Frank, >>>> >>>> >>>> >>>> If I recall right, it is not written in the ioam data draft. >>>> >>>> Yes, node by node configuration is an easy way. In the >>>> draft-zhou-ippm-ioam-yang, we have the “protocol-type” to indicate >>>> the layering. >>>> >>>> +--rw ioam >>>> >>>> +--rw ioam-profiles >>>> >>>> +--rw enabled? boolean >>>> >>>> +--rw ioam-profile* [profile-name] >>>> >>>> +--rw profile-name string >>>> >>>> +--rw filter >>>> >>>> | +--rw filter-type? ioam-filter-type >>>> >>>> | +--rw acl-name? -> /acl:acls/acl/name >>>> >>>> +--rw protocol-type? ioam-protocol-type >>>> >>>> +--rw incremental-tracing-profile {incremental-trace}? >>>> >>>> | ... >>>> >>>> +--rw preallocated-tracing-profile {preallocated-trace}? >>>> >>>> | ... >>>> >>>> +--rw pot-profile {proof-of-transit}? >>>> >>>> | ... >>>> >>>> +--rw e2e-profile {edge-to-edge}? >>>> >>>> ... >>>> >>>> >>>> >>>> >>>> >>>> Tianran >>>> >>>> From: Frank Brockners (fbrockne) [mailto:[email protected]] >>>> Sent: Monday, April 16, 2018 4:51 PM >>>> To: Tianran Zhou <[email protected]>; Mickey Spiegel >>>> <[email protected]>; Tom Herbert <[email protected]> >>>> Cc: NVO3 <[email protected]>; [email protected]; Service Function >>>> Chaining IETF list <[email protected]>; IETF IPPM WG <[email protected]> >>>> Subject: RE: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> >>>> >>>> >>>> Hi Tianran, >>>> >>>> >>>> >>>> IOAM is a domain specific feature (see also >>>> draft-ietf-ippm-ioam-data-02 sections 3 and 4), which allows an >>>> operator to control by means of configuration where and for which >>>> traffic IOAM data fields are added/updated/removed from the customer >>>> traffic. Using your example of Geneve over IPv6 – with IOAM data in >>>> both the Geneve and the IPv6 protocol, one would expect that the >>>> operator configures the endpoints of the Geneve tunnel to operate on >>>> the IOAM data in Geneve, and the IPv6 routers that the Geneve tunnel >>>> >>>> traverses to operate on the IOAM data in IPv6. >>>> >>>> >>>> >>>> >>>> Frank >>>> >>>> >>>> >>>> From: Tianran Zhou <[email protected]> >>>> Sent: Montag, 16. April 2018 10:37 >>>> To: Frank Brockners (fbrockne) <[email protected]>; Mickey Spiegel >>>> <[email protected]>; Tom Herbert <[email protected]> >>>> Cc: NVO3 <[email protected]>; [email protected]; Service Function >>>> Chaining IETF list <[email protected]>; IETF IPPM WG <[email protected]> >>>> Subject: RE: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> >>>> >>>> >>>> Hi Frank, >>>> >>>> >>>> >>>> How does a forwarder know when and where to insert the data? >>>> >>>> In the case of Geneve over IPv6, do you mean the device need to scan >>>> all the protocol stack? Or just the outer encapsulation? >>>> >>>> >>>> >>>> Tianran >>>> >>>> >>>> >>>> From: ippm [mailto:[email protected]] On Behalf Of Frank >>>> Brockners >>>> (fbrockne) >>>> Sent: Monday, April 16, 2018 3:08 PM >>>> To: Mickey Spiegel <[email protected]>; Tom Herbert >>>> <[email protected]> >>>> Cc: NVO3 <[email protected]>; [email protected]; Service Function >>>> Chaining IETF list <[email protected]>; IETF IPPM WG <[email protected]> >>>> Subject: Re: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> >>>> >>>> >>>> >>>> >>>> Tom, >>>> >>>> >>>> >>>> a quick addition to what Mickey mentioned below: What you seem to >>>> have in mind is what draft-ietf-ippm-ioam-data-02 refers to as “layering” >>>> (see section 3.), i.e. if you’re running for example Geneve over >>>> IPv6, then IOAM data could be encapsulated in both protocols, Geneve >>>> and >>>> IPv6 – giving you visibility into the “underlay” (IPv6) and the “overlay” >>>> >>>> (Geneve). >>>> >>>> >>>> >>>> >>>> Frank >>>> >>>> >>>> >>>> From: ippm <[email protected]> On Behalf Of Mickey Spiegel >>>> Sent: Freitag, 13. April 2018 20:22 >>>> To: Tom Herbert <[email protected]> >>>> Cc: NVO3 <[email protected]>; [email protected]; Service Function >>>> Chaining IETF list <[email protected]>; IETF IPPM WG <[email protected]> >>>> Subject: Re: [ippm] [Int-area] encapsulation of IOAM data in various >>>> protocols - follow up from WG discussion in London >>>> >>>> >>>> >>>> Tom, >>>> >>>> >>>> >>>> On Thu, Apr 12, 2018 at 10:17 PM, Tom Herbert <[email protected]> wrote: >>>> >>>> Mickey, >>>> >>>> Looking at these ippm drafts more closely, I have a much more >>>> fundamental concern. >>>> >>>> In draft-brockners-ippm-ioam-geneve-00 for instance, there is the >>>> text in the introduction: >>>> >>>> "In-situ OAM (IOAM) records OAM information within the packet while >>>> the packet traverses a particular network domain. The term "in-situ" >>>> refers to the fact that the IOAM data fields are added to the data >>>> packets rather than is being sent within packets specifically >>>> dedicated to OAM. This document defines how IOAM data fields are >>>> transported as part of the Geneve [I-D.ietf-nvo3-geneve] >>>> encapsulation." >>>> >>>> I assume this means that as packets with Geneve encapsulation >>>> traverse the network they are interpreted by intermediate nodes as >>>> being Geneve. Since Geneve is a UDP encapsulation, then the >>>> destination UDP port number would be used to identify packets as >>>> being Geneve. So an intermediate device might be looking for UDP >>>> packets destined to port >>>> 6081 (the assigned UDP port for Geneve). If my understanding is >>>> correct, then this is a problem. >>>> >>>> UDP port numbers do not have global meaning. An intermediate device >>>> may very well see UDP packets destined to port 6081 that are not >>>> actually Geneve. This scenario is discussed in RFC7605: >>>> >>>> "...intermediate device interprets traffic based on the port number. >>>> It is important to recognize that any interpretation of port numbers >>>> -- except at the endpoints -- may be incorrect, because port numbers >>>> are meaningful only at the endpoints." >>>> >>>> If the UDP data is modified, as the draft would imply, then >>>> misinterpretation may also mean silent data corruption of packets. A >>>> protocol that would allow this seems pretty incorrect! Note that >>>> this would be true also for any UDP encapsulation that the network >>>> tries to interpret. >>>> >>>> >>>> >>>> The intention is to allow for multiple nodes that a packet traverses >>>> >>>> to be able to insert IOAM node information in the same trace option, >>>> >>>> but leave some flexibility regarding which nodes actually do the >>>> >>>> IOAM processing and the node information. This may vary >>>> >>>> depending on the transport. >>>> >>>> >>>> >>>> In case of a tunneled encapsulation such as Geneve or VXLAN, >>>> >>>> there may still be multiple hops. For example a network may use >>>> >>>> Geneve or VXLAN, but only do L2 processing at ToRs, with L3 >>>> >>>> processing done at aggregation or core switches. In this case >>>> >>>> many packets would do 2 Geneve or VXLAN hops, so the packet >>>> >>>> would contain IOAM node information from two nodes. >>>> >>>> >>>> >>>> Another example is service function chaining using Geneve or >>>> >>>> VXLAN rather than NSH. >>>> >>>> >>>> >>>> >>>> I am also wondering if hop-by-hop options been considered for this >>>> application? Their interpretation in the network is unabiguous and >>>> they also have the advantage that the work with any IP protocol or >>>> encapsulation. >>>> >>>> >>>> >>>> IPv6 hop-by-hop options has been considered. See >>>> >>>> draft-brockners-inband-oam-transport-05. This has not yet been >>>> >>>> broken out into a separate draft. >>>> >>>> >>>> >>>> Mickey >>>> >>>> >>>> >>>> >>>> Thanks, >>>> Tom >>>> >>>> >>>> On Thu, Apr 12, 2018 at 3:31 PM, Mickey Spiegel >>>> <[email protected]> wrote: >>>> >>>> Tom, >>>> >>>> On Thu, Apr 12, 2018 at 2:46 PM, Tom Herbert <[email protected]> wrote: >>>> >>>> >>>> On Thu, Apr 12, 2018 at 9:54 AM, Greg Mirsky >>>> <[email protected]> >>>> wrote: >>>> >>>> Hi Frank, >>>> thank you for sharing your points. Please find my notes in-line >>>> and tagged >>>> GIM>>. I believe that this is very much relevant to work of >>>> GIM>>other >>>> working >>>> groups that directly work on the overlay encapsulations in the >>>> center of the discussion and hence I've added them to the list. >>>> Hope we'll have more opinions to reach the conclusion that is >>>> acceptable to all. >>>> >>>> Regards, >>>> Greg >>>> >>>> On Wed, Apr 11, 2018 at 12:02 PM, Frank Brockners (fbrockne) >>>> <[email protected]> wrote: >>>> >>>> >>>> Back at the IPPM meeting in London, we discussed several drafts >>>> dealing with the encapsulation of IOAM data in various >>>> protocols (draft-brockners-ippm-ioam-vxlan-gpe-00, >>>> draft-brockners-ippm-ioam-geneve-00, >>>> draft-weis-ippm-ioam-gre-00). One discussion topic that we >>>> decided to take to the list was the question on whether >>>> draft-ooamdt-rtgwg-ooam-header could be leveraged.. After >>>> carefully considering draft-ooamdt-rtgwg-ooam-header, I came to >>>> the conclusion that the “OOAM header” does not meet the needs >>>> of >>>> IOAM: >>>> >>>> * Efficiency: IOAM adds data to live user traffic. As such, an >>>> encapsulation needs to be as efficient as possible. The “OOAM header” >>>> is 8 >>>> bytes long. The approach for IOAM data encapsulation in the >>>> above mentioned drafts only requires 4 bytes. Using the OOAM >>>> header approach would add an unnecessary overhead of 4 bytes – >>>> which is significant. >>>> >>>> Greg, >>>> >>>> I'm missing something here. I looked at the drafts you referenced >>>> and each of them looks like the overhead for OAM is greater that >>>> four bytes. In each there is some overhead equivalent to >>>> type/length, for instance in Geneve four bytes are needed for >>>> option class, type, and length. Unless the the OAM data is zero >>>> length, I don't see how this adds up to only four bytes of overhead. >>>> >>>> >>>> >>>> The four versus eight bytes just refers to the fields in the four >>>> bytes of IOAM info, that is common to all IOAM options. Beyond >>>> that, there are IOAM option specific fields. For example if doing >>>> one of the IOAM trace options, there are four bytes of trace option >>>> header, including the IOAM-trace-type, NodeLen, Flags, and >>>> RemainingLen fields. These are followed by the node data list >>>> containing the per hop IOAM information. >>>> >>>> In looking at the OOAM header content, it has nothing to do with >>>> any of the IOAM information after the first four bytes. It contains >>>> another variant of the information in the first four bytes of IOAM >>>> info, spread out over eight bytes. >>>> >>>> >>>> Tom >>>> >>>> >>>> GIM>> The difference in four octets is because OOAM Header: >>>> >>>> provides more flexibility, e.g. Flags field and Reserved fields; >>>> >>>> >>>> >>>> The flags field only has one defined flag at the moment, for a >>>> timestamp block. For IOAM trace we need per hop timestamps, which >>>> the timestamp block cannot address, i.e. the timestamp block is >>>> redundant for >>>> >>>> IOAM. >>>> >>>> >>>> >>>> supports larger OAM packets than iOAM header; >>>> >>>> >>>> >>>> For IOAM purposes, 1020 octets is more than enough. >>>> >>>> >>>> is future proof by supporting versioning (Version field). >>>> >>>> >>>> >>>> IMO, taking the first two bits of the IOAM-Type to define a Version >>>> field would be a good thing. This does not require adding four more >>>> bytes of overhead. 64 IOAM-Types is more than enough. >>>> >>>> >>>> >>>> * Maturity: IOAM has several implementations, which were also >>>> shown at recent IETF hackathons – and we’re expecting >>>> additional implementations to be publicized soon. Interoperable >>>> implementations need timely specifications. Despite the >>>> question being asked, the recent thread on OOAM in the NVO3 >>>> list hasn’t revealed any implementation of the OOAM header. >>>> In >>>> addition, the thread revealed that several fundamental >>>> questions about the OOAM header are still open, such as whether >>>> or how active OAM mechanisms within protocols such as Geneve >>>> would apply to the OOAM header. This ultimately means that we >>>> won’t get to a timely specification. >>>> >>>> >>>> GIM>> May I ask which encapsulations supported by the >>>> GIM>> implementations >>>> you >>>> refer to. Until very recently all iOAM proposals were to use >>>> meta-data TLV in, e.g. Geneve and NSH. And if these or some of >>>> these implementations already updated to the newly proposed iOAM >>>> shim, I don't see problem in making them use OOAM Header. Would >>>> you agree? >>>> >>>> >>>> * Scope: It isn’t entirely clear to which protocols the OOAM >>>> header would ultimately apply to. The way the OOAM header is >>>> defined, OOAM uses a 8-bit field for “Next Prot”, the next >>>> protocol. Some protocols that IOAM data needs to be >>>> encapsulated into use 16-bits for their next protocol code points. See e.g. >>>> the GRE encapsulation – as specified in >>>> draft-weis-ippm-ioam-gre-00. >>>> >>>> >>>> GIM>> The first paragraph of the Introduction section states: >>>> New protocols that support overlay networks like VxLAN-GPE >>>> [I-D.ietf-nvo3-vxlan-gpe], GUE [I-D.ietf-nvo3-gue], Geneve >>>> [I-D.ietf-nvo3-geneve], BIER >>>> [I-D.ietf-bier-mpls-encapsulation], >>>> >>>> and >>>> >>>> NSH [I-D.ietf-sfc-nsh] support multi-protocol payload, e.g. >>>> Ethernet, IPv4/IPv6, and recognize Operations, Administration, and >>>> Maintenance (OAM) as one of distinct types. That ensures that >>>> Overlay OAM (OOAM)packets are sharing fate with Overlay data packet >>>> traversing the underlay. >>>> I'm updating the OOAM Header draft and along with cleaning nits >>>> will update reference to GUE. I think that the list and the >>>> statemnt are quite clear in identifying the scope of networks >>>> that may benefit from using not only common OOAM Header but >>>> common OOAM mechanisms, e.g. Echo Request/Reply. >>>> >>>> With the above in mind, I’d suggest that the WG moves forward >>>> with specific definitions for encapsulating IOAM data into >>>> protocols – per the above mentioned drafts. >>>> >>>> >>>> >>>> Regards, Frank >>>> >>>> >>>> _______________________________________________ >>>> ippm mailing list >>>> [email protected] >>>> https://www.ietf.org/mailman/listinfo/ippm >>>> >>>> >>>> >>>> _______________________________________________ >>>> Int-area mailing list >>>> [email protected] >>>> https://www.ietf.org/mailman/listinfo/int-area >>>> >>>> >>>> _______________________________________________ >>>> ippm mailing list >>>> [email protected] >>>> https://www.ietf.org/mailman/listinfo/ippm >>>> >>>> >>>> >>>> >>>> >>>> >>>> _______________________________________________ >>>> sfc mailing list >>>> [email protected] >>>> https://www.ietf.org/mailman/listinfo/sfc >>>> >>>> _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
