Re: [DNA] Comments on DNAv6 (draft-dnadt-dna-protocol-00.txt)

[Subba Reddy <subbareddy@samsung.com>]

Hi Erik,

Thanks for input.

Please see below...


> Subba Reddy wrote:
> > Hi,
> >
> > few comments and questions on the DNAv6 draft.

> > 2. While bootstrapping DNA data structures(section 5.1.3), a) will
> > the router reply for RSs without landmark option (may be sent by
> > other routers) b) will the router reply for RSs that contains
> > landmark option (may be sent by DNA host)
>
> I think the current text says that it will not respond at all. This is a
> bit suboptimal when multiple routers boot at the same time.
> I suspect we need to figure out how to tweak this.
> Suggestions?
>

I think, it may be better to reply with normal RA (like RFC 2461) during
bootstrapping.
With this, If more than one router is bootstrapping, routers can know each
others prefixes.
It may help even the hosts to learn the prefixes of the new router fast.

> > 4. In section 5.2.4,
> >
> > ".....If the unicast Router Advertisement contains a Landmark option
> > that matches the Landmark Option in the last transmitted Router
> > Solicitation ....."
> >
> > Is a case where, a unicast router advertisement comes without
> > landmark option is possible? (DNA routers which are bootstrapping may
> > just send RA) If possible, some text which tells what to do in such
> > cases may need to be added.
>
> We should probably say what to do in any case, since an existing RFC
> 2461 router is free to unicast RAs (even if the RFC suggests to always
> multicast them)
>

Yes. It may be better to add the text for this case.

> > 5. To deal with amplification effect, what about having a threshold
> > on number of routers sending fast RA? For example, only first 5
> > routers (as per the fast RA rankings) only will reply for RSs (in
> > addition to the method specified in the draft)
>
> That might make sense.
>
> I assume the 6+ ranked routers would not be completely quiet, but
> instead schedule a 3 second multicast RA. This is needed in the case
> that the routers annouce different prefixes, and also to make the host
> discover that it has >5 default routers.
>

Yes. 6+ ranked routers need to schedule the multicast even though token
is available.

>     Erik
>
>

Thanks & Regards,
Subba Reddy