Re: [Roll] Topics and drafts within Roll charter

Hello Peter:

I encourage the WG to consider your list carefully and respond.

My personal priorities would be:

1) Item 4. This deals with actual field problems, and is a preerq for the Join Process that 6TiSCH is working on. Michael has a draft and I'm willing to contribute together with Charlie from Cisco.
2) item 2+5, seem to be the same to me. This is a rather easy work once rfc6775-update is passed and I'm willing to start/contribute

Take care,

Pascal

-----Original Message-----
From: Roll [mailto:roll-bounces@ietf.org] On Behalf Of peter van der Stok
Sent: lundi 9 octobre 2017 09:47
To: Roll <roll@ietf.org>
Subject: [Roll] Topics and drafts within Roll charter

Hi Roll,

In a discussion with Rahul and Pascal, it transpires that there are still many topics to address that fit within our charter. The proliferation of topics worries us a bit. We have only a limited number of active authors and some topics also seem to be competing. The result of this situation might be that we have an overflowing work agenda. 
Therefore, we need to find additional people to work on those topics; or reduce the number of topics.
It is our suggestion that we discuss these topics, find dedicated authors, and prioritize them  after some debate on the M-L.
Also we should like to remove the competitive subjects by joining them into one draft.

Your comments please.

Ines + Peter

------------------------ List of topics
------------------------------------------

1 Route invalidation as a standalone topics The topic is mentioned in several drafts, but we need to come to one general approach.

2.A draft that allows a ND only device to connect, be reachable and move in a RPL network.

3. Not all implementers are aware of the design issues of storing mode of RPL vs non-storing. Both of the modes have issues with their design. 
Some
issues are getting sorted out by drafts such as dao-projection and no-path DAO optimization. But still considerable design issues need to be handled. To name few:
a. handling parent switching optimally in storing MOP. Currently with Storing MOP it would lead to DIO/DAO storm in the sub-path from the child node who switches the parent. This is handled well in NS MOP (Non-storing MOP).
b. how to handle node(6ln, 6lr, lbr) reboot scenario? In some cases it is trivial, but in most cases it is not (considering dependence on several state variables such as DTSN across reboots)! Also for practical point of view, need to consider that writing to flash/NV-memory is not a good option in embedded devices and should be avoided as far as possible.
c. Problems of current DAO-ACK in storing MOP. There was a discussion on ML long time back, but there is no draft in the space.
d. problem of bulging IPv6 headers in NS MOP. Most part of this will be taken care of by SRH compression and dao-projection.

4. Confusion between DAG selection (for joining and jumping) vs. parent selection (for re-parenting within a DODAG). 6TiSCH has isolated the need for a join preference which is different from the Rank used in parent selection. The resulting Rank may be used in the join preference, but not only. The size of the DODAG, the number of children of that parent, etc... may influence. There is basically the need for a new sort of objective function, this time in order to select a DODAG to join.

5. Integration with 6LoWPAN. We need to write that draft that standardizes the procedures suggested in the 6TiSCH architecture and shows a non RPL aware joining a DODAG and moving inside. With the new 6LoWPAN ND and the NP DAO, we now have all the tools to do it. Unless we consider that the reference is the 6TiSCH architecture in which case we complete the design there.

6. Exposing (some of) the structure of the Mesh to the root to enable the DAO projection for transversal routes and in storing mode in general.

7. Using bitmaps for multicast and unicast routing, used in
  7a routing tables, or 7b in header for source routing

8. Guidance to implementers who are relatively new to RPL are not aware of many design considerations and there should be a doc which talks about it. Similar work is started in
https://tools.ietf.org/html/draft-clausen-lln-rpl-experiences-09 ... but it does not list all the issues imo.

9. What to do with expired YANG model drafts

10. What else do you think that we should consider?

--
Peter van der Stok
vanderstok consultancy
mailto: consultancy@vanderstok.org
www: www.vanderstok.org
tel NL: +31(0)492474673     F: +33(0)966015248

_______________________________________________
Roll mailing list
Roll@ietf.org
https://www.ietf.org/mailman/listinfo/roll