Re: [Roll] FW: New Version Notification for draft-thubert-roll-eliding-dio-information-01.txt

["Li Zhao (liz3)" <[e-mail]>]

Hello Authors,

After reviewing this draft, I have some concerns as following:

1. In section 5
   >If the link MTU does not permit to send a single DIO message with all the options packaged then the options may be spread over multiple consecutive DIO messages with the same RCSS that are sent in a rapid sequence.

What about the case that child lost one of the fragment? E.g. parent sends RIO/DCO/RIO in three packets because of MTU, child lost DCO. Next time, parent only sends out AOO with the same RCSS. So this child need to wait SEQUENCE_WINDOW for next time's full option advertisement.

2. Is AOO necessary? If DIO can fragment options and don't always send all options, can we use DIO without options to indicate the AOO? 
    The shortest DIO Base Object without DODAGID is only 8 bytes.

3. In section 6
> A child can resynchronize any of the protected options to the latest RCSS by sending a DIS Message to a candidate parent that advertises that RCSS in DIO messages. 
> The child MUST set the desired combination of 'R', 'D', 'P', 'M' and 'O' flags to indicate the option(s) that it needs updated.

Is there a case that root removes some options such as GCO after network formed? If so, parent may stop sending GCO and increment RCSS, how does child know that it should stop request GCO?


Best regards,
Li

On 2019/10/17, 23:51, "Roll on behalf of Pascal Thubert (pthubert)" <[e-mail] on behalf of [e-mail]> wrote:

    Dear all:
    
    This update clarifies the use of the new DIO sequence counter and the method to pull the update from a  parent.
    Comments welcome!
    
    Pascal
    
    -----Original Message-----
    From: [e-mail] <[e-mail]> 
    Sent: jeudi 17 octobre 2019 17:46
    To: Pascal Thubert (pthubert) <[e-mail]>; Rahul Jadhav <[e-mail]>; Rahul Arvind Jadhav <[e-mail]>; Dominique Barthel <[e-mail]>
    Subject: New Version Notification for draft-thubert-roll-eliding-dio-information-01.txt
    
    
    A new version of I-D, draft-thubert-roll-eliding-dio-information-01.txt
    has been successfully submitted by Pascal Thubert and posted to the IETF repository.
    
    Name:		draft-thubert-roll-eliding-dio-information
    Revision:	01
    Title:		Eliding and Querying RPL Information
    Document date:	2019-10-17
    Group:		Individual Submission
    Pages:		13
    URL:            https://www.ietf.org/internet-drafts/draft-thubert-roll-eliding-dio-information-01.txt
    Status:         https://datatracker.ietf.org/doc/draft-thubert-roll-eliding-dio-information/
    Htmlized:       https://tools.ietf.org/html/draft-thubert-roll-eliding-dio-information-01
    Htmlized:       https://datatracker.ietf.org/doc/html/draft-thubert-roll-eliding-dio-information
    Diff:           https://www.ietf.org/rfcdiff?url2=draft-thubert-roll-eliding-dio-information-01
    
    Abstract:
       This document presents a method to safely elide a group of global RPL
       options by synchonizing the state associated with each of these
       options between parent and child using a new sequence counter in DIO
       messages.  A child that missed a DIO message with an update of any of
       those protected options detects it by the change of sequence counter
       and queries the update with a DIS Message.
    
                                                                                      
    
    
    Please note that it may take a couple of minutes from the time of submission until the htmlized version and diff are available at tools.ietf.org.
    
    The IETF Secretariat
    
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