No. It was more in reference to your comment about blocking this document.
 If a draft is brought into WG, it goes through regular process.

> On Nov 4, 2015, at 8:18 PM, Liyizhou <[email protected]> wrote:
> 
> WG do not own the base encapsulation so they can't even work on it. That 
> seems the implication?
>  
> Yizhou
>  
>  
> 发件人: Sam Aldrin [mailto:[email protected]] 
> 发送时间: 2015年11月5日 10:14
> 收件人: Liyizhou
> 抄送: Tom Herbert; Haoweiguo; Shahram Davari; [email protected]; Dacheng Zhang; 
> Deepak Kumar (dekumar)
> 主题: Re: [nvo3] draft-­-pang-­-nvo3-­-vxlan-­-path-­-detection-­-01
>  
> Just so you know, VXLAN RFC was not WG document, rather independent 
> submission.
> As you are bringing this to NVo3 WG and asking for comments, they are given.
> There is nothing wrong in either direction, unless you feel it that way.
>  
> -sam
>  
> On Wed, Nov 4, 2015 at 5:46 PM, Liyizhou <[email protected] 
> <mailto:[email protected]>> wrote:
> RFC7348 VxLAN itself is an informational document. IMO, being informational 
> does not necessarily mean no new bit can be defined. The document can be 
> improved to clearly state the applicable scenario and compatibility 
> considerations. However the historical procedural issue should not be the 
> only or major reason to block the progressing of such kind of documents. I do 
> not see anything wrong to proceed it with informational in this case given 
> there exists a clear requirement and reasonable deployment from it.
> 
> 
> Thanks,
> Yizhou
> 
> 
> -----邮件原件-----
> 发件人: nvo3 [mailto:[email protected] <mailto:[email protected]>] 代表 
> Tom Herbert
> 发送时间: 2015年11月5日 6:05
> 收件人: Haoweiguo
> 抄送: Sam Aldrin; Shahram Davari; [email protected] <mailto:[email protected]>; Dacheng 
> Zhang; Deepak Kumar (dekumar)
> 主题: Re: [nvo3] draft--pang--nvo3--vxlan--path--detection--01
> 
> On Wed, Nov 4, 2015 at 9:31 PM, Haoweiguo <[email protected] 
> <mailto:[email protected]>> wrote:
> > Hi Sam,
> >
> > The extra bit in VXLAN reserved field has no side effect on regular
> > VXLAN forwarding process. The hardware requirements for intermediate
> > nodes is also low, the intermediate nodes only need to grab the data
> > packets with the OAM flag to control plane using regular ACL, most
> > current commertial chipsets can support this behavior.
> >
> 
> "The extra bit in VXLAN reserved field has no side effect on regular VXLAN 
> forwarding process."-- I think this is an assumption based on what 
> implementations are probably doing currently as opposed to what is specified 
> by the protocol. The VXLAN RFC does not specify a forwarding process AFAICT. 
> And, as I mentioned yesterday, VXLAN is not extensible in its current 
> definition.  Unknown reserved bits must be ignored on reception which means 
> that a receiver that doesn't support PD bit will assume that the payload is 
> an Ethernet packet and attempt to deliver it as such.
> 
> Given that this is not the first time someone has tried to extend VXLAN and 
> it's wide deployment, it might be prudent to try to define a method to extend 
> the protocol without breaking compatibility. The pseudo packet (cannot just 
> be called a header) trick will work if the packet is created such that it is 
> guaranteed to be dropped at a receiver that doesn't understand the extensions 
> (e.g. put a zero in total length field in case of IP). Obviously any method 
> should support more than just one extension. This implies that fields must be 
> precisely ordered, so for an implementation to parse field, it must be able 
> to calculate the offset of the field. So the order that fields are defined in 
> VXLAN becomes important and needs to be spelled out.
> The current placement of the PD bit probably would have to change for 
> instance. The easiest thing to do is define the flag bits left to right, 
> where to process the n'th bit an implementation must understand the first n-1 
> bits (see GRE or GUE), but the n+1 bits and beyond can still be ignored.
> 
> Tom
> 
> 
> 
> The pseudo header trick for extensibility might work
> > Thanks,
> >
> > weiguo
> >
> > ________________________________
> > From: Deepak Kumar (dekumar) [[email protected] <mailto:[email protected]>]
> > Sent: Wednesday, November 04, 2015 14:51
> > To: Sam Aldrin
> > Cc: Shahram Davari; [email protected] <mailto:[email protected]>; Dacheng Zhang
> >
> > Subject: Re: [nvo3]
> > draft-­-pang-­-nvo3-­-vxlan-­-path-­-detection-­-01
> >
> > HI Sam,
> >
> > Vxlan field that is used is reserved field and so existing Asic based
> > hardware won't add this in transmit but receiving packet with reserved
> > bit set has no side effect.
> > If hardware is programmable their is no issue even in transmit.
> >
> > Can you give me example of any Asic implementation which will have
> > problem, we can add text for user to be careful before turning  on the 
> > solution.
> >
> > We can even call this extension of vxlan with pd bit.
> >
> > Thanks,
> > Deepak
> >
> > Sent from my iPhone
> >
> > On Nov 4, 2015, at 3:09 PM, Sam Aldrin <[email protected] 
> > <mailto:[email protected]>> wrote:
> >
> > Hi Deepak,
> >
> > Aren’t you or aren’t you not changing the packet format by introducing
> > PD flag bit in the reserved field. i.e changing RFC7348?
> > If so, how can you claim to be informational? Is it because RFC is
> > informational?
> >
> > For ex, VXLAN-GPE is in standards track, although it is now in expired
> > state.
> >
> > Irrespective of technical differences, if a specific format is being
> > changed, it will impact existing future deployments as well,
> > informational or not.
> > Being informational does not avoid that.
> >
> > -sam
> >
> > On Nov 3, 2015, at 8:03 PM, Deepak Kumar (dekumar) <[email protected] 
> > <mailto:[email protected]>>
> > wrote:
> >
> > HI Sam,
> >
> > This is good discussion and we are bringing this draft as
> > informatiinal draft for narrow scenario for some operators but not for 
> > other operators.
> >
> > Ttl solution is too slow at scale and instead of argument we can give
> > data of how much time it takes but for some operator that amount of
> > time is okay but for some they have will want it to complete it
> > quickly. As this being informational solution it's brought to working
> > group as hardware driven controller controlled scenario and make its
> > language may and should so all the issues it may cause to software vtep can 
> > be fixed.
> >
> > Why can't software based and hardware based solution co-exist when
> > information draft won't force everyone to implement it.
> >
> > Thanks
> > Deepak
> >
> > Sent from my iPhone
> >
> > On Nov 4, 2015, at 12:41 PM, Sam Aldrin <[email protected] 
> > <mailto:[email protected]>> wrote:
> >
> > Hi Deepak,
> >
> > What you are describing is very narrow scenario, which has its own pitfalls.
> > Inline for my comments.
> >
> > On Nov 3, 2015, at 7:10 PM, Deepak Kumar (dekumar) <[email protected] 
> > <mailto:[email protected]>>
> > wrote:
> >
> > Hi Shahram/Sam,
> >
> > This solution is hardware centric with controller and policy needs to
> > be created on each hop.
> > This solution is not applicable for all scenarios.
> >
> > Policy example
> > Match peer vtep ip == destination ip of packet destination  port 4789,
> > pd bit action punt and drop.
> > Match peer vtep ip!=destination ip destination port == 4789, pd bit
> > action punt and forward.
> >
> > If you want to employ policy for every vtep and on every device in the
> > network, IMO, a bad design to start with.
> >
> >
> > Now drop takes care of leak scenario from leafs.
> >
> >
> > Now controller eats up the packet so no issue of loop.
> > Also in network packet is going as data packet as per vxlan rule of
> > max ttl so not sure where's loop.
> >
> > You mean there cannot be loops in n/w, just because TTL is used? (loop
> > life is dependent on ttl)
> >
> > If loop is there oam and data both will suffer.
> >
> > Yes both will suffer. You use OAM to detect whether data plane has
> > problem or not. With this, it will compound the problem.
> >
> >
> > Loop with controller can be avoided but that's outside the scope.
> >
> >
> > Alibaba is also operator and using this data center for cloud services.
> >
> > I agree Ttl expiry will also work but that's software solution and
> > separate draft not this draft intention.
> >
> > If you already have a solution, why invent a new one? Are you saying
> > controller is not efficient and cannot perform oam efficiently with
> > existing ttl mechanism? :D
> >
> >
> > On Concern of policy application controller will apply the policy and
> > if network is not hardware oam capable they won't initiate it and use
> > software oam method.
> >
> > Well, you have the answer right there.
> > In other words, if a device cannot support your proposed solution, you
> > will revert back to ttl solution. why don’t you just use that solution 
> > instead?
> >
> >
> > We evaluated multiple Asic and found out solution can be done on
> > multiple broadcom and custom Asic and Alibaba network is running on 2
> > different Broadcom Asic.
> >
> > And your point being? :D
> >
> > -sam
> >
> >
> > Thanks
> > Deepak
> >
> > Sent from my iPhone
> >
> > On Nov 4, 2015, at 11:29 AM, Sam Aldrin <[email protected] 
> > <mailto:[email protected]>> wrote:
> >
> > I expressed the same concern at last IETF meeting, as Shahram raised here.
> > Haven’t gotten the  explanation yet.
> >
> > If TTL expiry mechanism is used, then the definition of IP TTL will
> > have to be redefined in order to make a copy and forward to next hop.
> > But if L3 devices have to read into VXLAN header to determine OAM bit
> > is set, they need to implement DPI for the same.
> >
> > Secondly, imagine when there exists a loop. In fact, they do exist
> > even in controller based networks.
> >
> > Speaking as an operator, as mentioned yesterday, this will cause
> > packet storm and unintended consequences.
> >
> > Why are we solving the problem when it doesn’t exist?
> >
> > -sam
> >
> > On Nov 3, 2015, at 6:02 PM, Shahram Davari <[email protected] 
> > <mailto:[email protected]>> wrote:
> >
> > I think your assumption is broken. But you have an alternative method
> > and that is using TTL expiry.
> >
> > Thx
> > SD
> >
> > From: Dacheng Zhang [mailto:[email protected] 
> > <mailto:[email protected]>]
> > Sent: Tuesday, November 03, 2015 5:53 PM
> > To: Shahram Davari; [email protected] <mailto:[email protected]>
> > Subject: Re: [nvo3]
> > draft-­-pang-­-nvo3-­-vxlan-­-path-­-detection-­-01
> >
> > This draft actually proposes a mechanism where the intermediates are
> > required to recognize the vxlan oam packets. If this assumption is
> > broken, the solutions proposed in this draft may not be effective.
> >
> > Cheers
> >
> > Dacheng
> >
> > 发件人: nvo3 <[email protected] <mailto:[email protected]>> on behalf 
> > of Shahram Davari
> > <[email protected] <mailto:[email protected]>>
> > 日期: 2015年11月4日 星期三 上午9:33
> > 至: "[email protected] <mailto:[email protected]>" <[email protected] 
> > <mailto:[email protected]>>
> > 主题: [nvo3] draft-­‐pang-­‐nvo3-­‐vxlan-­‐path-­‐detection-­‐01
> >
> > Hi,
> >
> > This draft needs to address how intermediate L3 routers are going to
> > see these VXLAN OAM packets, since L3 routers just do L3 routing and
> > don’t look at the payload to see it is VXLAN and then see that these
> > are PD OAM packets. The only option I can think of is TTL expiry,
> > otherwise it won’t work, the way it is defined now,
> >
> > Thx
> > Shahram
> > _______________________________________________ nvo3 mailing list
> > [email protected]https://www.ietf.org/mailman/listinfo/nvo3 
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> >
> >
> >
> >
> >
> > _______________________________________________
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> >
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