Re: [Roll] DAO Projection - identifying storing, non-storing P-DAO

["Pascal Thubert (pthubert)" <[e-mail]>]

Hello Rahul:

As you figured, the original intent was to replace the TIO by a VIO. So yes, your proposal is workable.
An alternate could be to define a source-routed VIO (SRVIO) with Type = 0xB and keep the current VIO for storing mode only.

What do you think?

Pascal


> -----Original Message-----
> From: Rahul Jadhav <[e-mail]>
> Sent: mercredi 13 juin 2018 13:58
> To: Pascal Thubert (pthubert) <[e-mail]>
> Cc: Routing Over Low power and Lossy networks <[e-mail]>
> Subject: Re: DAO Projection - identifying storing, non-storing P-DAO
> 
> One thing that comes to my mind is using DAO base object bits... But i m not
> sure if they can/should be expended for such purpose.
> Another option is to use TIO bits and make TIO mandatory preceding the VIOs
> ... Other fields such as path-seq/lifetime can also be removed from VIO and
> can be kept only in TIO. Anyways having a different Path-Sequence in
> individual VIOs does not help (not sure if having a different path lifetime in
> individual VIO is needed?).
> For current implementation, i m planning to go ahead with an extra
> pass/traversal over the options to check for multiple VIOs.
>  On Wed, 13 Jun 2018 at 14:54, Pascal Thubert (pthubert)
> <[e-mail]> wrote:
> >
> > I agree Rahul,
> >
> > I picked that method as a starting point but as I presented at the IETF
> meeting I do not like it either, and it would be great that the group come up
> with something better.
> >
> > Would you have a particular preference based on your experience here?
> >
> > Pascal
> >
> >
> > > -----Original Message-----
> > > From: Rahul Jadhav <[e-mail]>
> > > Sent: mercredi 13 juin 2018 03:55
> > > To: Routing Over Low power and Lossy networks <[e-mail]>;
> > > Pascal Thubert (pthubert) <[e-mail]>
> > > Subject: DAO Projection - identifying storing, non-storing P-DAO
> > >
> > > Hello Pascal, WG,
> > >
> > > When i started implementing storing mode P-DAO, i faced one problem,
> > > ... as per the draft the only way to identify storing P-DAO from
> > > non-storing P-DAO is that storing P-DAO has at-least 2 VIOs whereas
> > > non-storing P-DAO has only one VIO.
> > > The problem with implementation is that i need to traverse the whole
> > > P-DAO before i know whether it is storing or non-storing P-DAO and
> > > populate the route table accordingly. This way either i have to
> > > buffer VIO/via temporarily and then act. Otherwise i have to have a
> > > 2-pass traversal through the P-DAO to check whether it is storing or
> > > non-storing first and then act on the fields in later pass.
> > >
> > > If we can have a flag somewhere in the P-DAO header to signal
> > > storing or non- storing then it would make implementation much simpler.
> > >
> > > For interested ones, part implementation of DAO projection code is at:
> > > https://github.com/whitefield-framework/contiki/tree/dao_projection
> > > It currently supports registration/unregistration of projected
> > > routes using non-storing P-DAO with +/- ACKing.
> > >
> > > Regards,
> > > Rahul