Re: [Roll] Clarification on the objective function

[Philip Levis <pal at cs.stanford.edu>]

On Nov 9, 2009, at 4:57 AM, Julien Abeille (jabeille) wrote:

> Hi Pascal,
>
> just to be sure I understand:
> - I have a preferred parent at rank 1, my rank is 5, I receive a DIO  
> for a parent rank 2, must i ignore it? I would say no as this node  
> is useful as backup parent, but if i lose my preferred parent,  
> choosing the backup as preferred will make my rank increase (this is  
> ok because if i compute rank based on all parents, I would have to  
> increase rank at reception of the second DIO anyway)
> - At boot time, I receive two DIOs (rank 1 and 2) before computing  
> OCP. If I calculate rank based on preferred only, if at some point I  
> would like to switch to the other parent, I will have to move down.
>
> Still I think it is preferable to calculate rank based on preferred  
> only, but what do other think?
> Julien

Julien,

Question 1: In -04, you MUST process the DIO. Section 5.4.2.1:

	If the rank of SRC as reported in the DIO message is lesser
        than that of the node within the DAG, then the DIO message MUST
        be considered for further processing

Question 2: The draft is unclear.

Phil