Re: A draft on the encapsulation of end-to-end IETF network slice information in IPv6 data plane

On Mon, May 24, 2021, 4:26 AM Dongjie (Jimmy) <jie.dong@huawei.com> wrote:

> Hi Ole,
>
> Thanks for your comment.
>
> It is expected that the identifiers defined in this draft will be parsed
> or processed by some network nodes along the path, rather than only the
> endpoints, thus maybe it is more convenient to carry them in the IPv6
> header. This could also reduce the overhead of introducing other tunnel
> layers to the IPv6 network.

A HBH option to provide acillary information for IPIP encapsulation makes a
lot of sense to me, however this proposed format wouldn't be extensible to
carry other type of information that might be of interest beyond a four
byte ID.

A way to make the format extensible could simply be to add a sixteen bit
flags that can indicate flag-fields like in GRE or GUE. This allow other
optional fields in option. Since HBH EH needs to be eight bytes anyway,
there's no additional overhead if this is only HBH option. Also, this is a
way to pack data into one option as opposed to using separate options (so
less overhead and limiting number of options in HBH EH is a good thing).

Tom

>
> Best regards,
> Jie
>
> > -----Original Message-----
> > From: otroan@employees.org [mailto:otroan@employees.org]
> > Sent: Friday, May 21, 2021 4:58 PM
> > To: Dongjie (Jimmy) <jie.dong@huawei.com>
> > Cc: 6man@ietf.org
> > Subject: Re: A draft on the encapsulation of end-to-end IETF network
> slice
> > information in IPv6 data plane
> >
> > Hi Jie,
> >
> > > Recently we published a draft on the encapsulation of end-to-end IETF
> > network slice information in IPv6 data plane:
> > >
> > >
> >
> https://datatracker.ietf.org/doc/html/draft-li-6man-e2e-ietf-network-slicing
> > >
> > > This document defines the mechanism of encapsulating the end-to-end
> > network slice related identifiers in IPv6 packet, which is aligned with
> the
> > framework as defined in draft-li-teas-e2e-ietf-network-slicing.
> >
> > What are the benefits of using an IPv6 extension header to carry the meta
> > data?
> > In contrast to embedding it in a tunnel header (like what GRE, Geneve,
> etc,
> > etc does).
> >
> > Best regards,
> > Ole
>
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