Re: [bess] [**EXTERNAL**] RE: CORRECTION WG Last Call, IPR and Implementation Poll for *draft-ietf-bess-evpn-geneve-03*

[Anoop Ghanwani <[e-mail]>]

Thanks Jorge.  I get it now.

On Sun, Dec 18, 2022 at 11:28 PM Jorge Rabadan (Nokia) <
[e-mail]> wrote:

> Hi Anoop,
>
>
>
> Note that it is not only the ESI-based filtering procedure (for
> multi-homing) that is performed using the information in the Ethernet
> option TLV, but also the E-Tree flags and the BUM indication. So even if
> you are using local-bias, and you are not using E-Tree, we still want the
> BUM indication to avoid transient packet duplication in certain scenarios.
>
>
>
> So IMO what we want is to RECOMMEND the use of the ethernet option TLV in
> all cases.
>
>
>
> Thanks.
>
> Jorge
>
>
>
> *From: *Anoop Ghanwani <[e-mail]>
> *Date: *Sunday, December 18, 2022 at 3:49 AM
> *To: *Boutros, Sami <[e-mail]>
> *Cc: *Boutros, Sami <sboutros=[e-mail]>, UTTARO, JAMES <
> [e-mail]>, Jorge Rabadan (Nokia) <[e-mail]>, Matthew
> Bocci (Nokia) <[e-mail]>, [e-mail] <[e-mail]>,
> [e-mail] <[e-mail]
> >
> *Subject: *Re: [bess] [**EXTERNAL**] RE: CORRECTION WG Last Call, IPR and
> Implementation Poll for *draft-ietf-bess-evpn-geneve-03*
>
> Here's a proposed change:
>
>
>
> OLD
>
>
> While "local-bias" MUST be supported along with Geneve encapsulation, the
> use of the Ethernet option-TLV is RECOMMENDED to follow the same procedures
> used by EVPN MPLS.
>
>
>
> NEW
>
>
>
> While "local-bias" MUST be supported along with Geneve encapsulation, the
> use of the Ethernet option-TLV is required if not using local-bias and
> instead following procedures used by EVPN MPLS.
>
>
>
> This allows implementations that implement only local bias to skip
> sending/implementing the TLV.
>
>
>
> Or are you trying to RECOMMEND that implementations also implement the
> EVPN MPLS procedures in addition to local bias?  If so, I would word the
> text as:
>
>
>
> While "local-bias" MUST be supported along with Geneve encapsulation and
> that doesn't require the use of the Ethernet option-TLV, it is RECOMMENDED
> that Geneve implementations also implement the same procedures used by EVPN
> MPLS.
>
>
>
> On Sat, Dec 17, 2022 at 6:33 PM Anoop Ghanwani <[e-mail]>
> wrote:
>
> Sami,
>
>
>
> Why is it recommended to carry the TLV if local bias is in use?  (I
> understand the need for it if we're not using local bias.)
>
>
>
> Anoop
>
>
>
> On Sat, Dec 17, 2022 at 2:06 PM Boutros, Sami <[e-mail]> wrote:
>
> I’m not sure what tightening you are recommending, I am out of ideas of
> how to tighten this, may be you can propose something.
>
>
>
> It is quite clear to me and to the authors, and I hope to everyone else,
> how the TLV can be used for SH as a mechanism similar to local bias, as
> well it can be used when ETREE support is needed.
>
>
>
> Thanks,
>
>
> Sami
>
> *From: *Anoop Ghanwani <[e-mail]>
> *Date: *Saturday, December 17, 2022 at 1:25 PM
> *To: *Boutros, Sami <[e-mail]>
> *Cc: *Boutros, Sami <sboutros=[e-mail]>, UTTARO, JAMES <
> [e-mail]>, Rabadan, Jorge (Nokia - US/Mountain View) <
> [e-mail]>, Bocci, Matthew (Nokia - GB) <
> [e-mail]>, [e-mail] <[e-mail]>,
> [e-mail] <[e-mail]
> >
> *Subject: *Re: [bess] [**EXTERNAL**] RE: CORRECTION WG Last Call, IPR and
> Implementation Poll for *draft-ietf-bess-evpn-geneve-03*
>
> Sami,
>
> I don't believe there was closure on this issue.
>
> I think the text around the option TLV being RECOMMENDED should be
> tightened so that it's recommended only when needed.  The way the draft is
> currently written, it sounds like it is recommending that the TLV always be
> carried if multihoming is in use.  But this is not necessary or even
> valuable if Local Bias is in use.
>
> On Wed, Jul 13, 2022 at 12:12 AM Anoop Ghanwani <[e-mail]>
> wrote:
>
> > Hi Sami,
> >
> > Thanks for updating the doc.
> >
> > Regarding this:
> > >>>
> >
> > I find this statement confusing
> >
> >
> >
> >    While "local-bias" MUST be supported along with GENEVE encapsulation,
> >
> >    the use of the Ethernet option-TLV is RECOMMENDED to follow the same
> >
> >    procedures used by EVPN MPLS.
> >
> >
> >
> >
> >
> > I'm not sure how it helps to carry an extra TLV when it is known
> >
> > that its absence or presence results in identical behavior.
> >
> >
> >
> > Sami: The new TLV is not there only for local bias! It is there for bum
> and leaf/root indications too. So, we can’t simply not carry it. As for the
> text above, we are saying setting the ESI label in the TLV will allow us to
> follow the same Split horizon behavior of MPLS-EVPN with no need for local
> bias. It is true local bias must be supported but this mechanism will work
> too if available given that it is optional.
> >
> > >>>
> >
> > I'm not sure I follow what you're saying.  The new TLV is actually not
> > needed for the Local Bias case because we already know how to make that
> > case work without it.  It is, however, needed for the non-Local Bias case
>
>