[Olsr-users] Doubts about Willingness, MPR Selection and Routing.

[Ferry Huberts]

MPR doesn't work properly in olsrd v1

Henning is working on v2, in which this should work properly

On 01/02/13 13:45, Alex López wrote:
> Hello,
>
> After reading some documentation about OLSR and testing it with OLSRd in
> OpenWRT I have some questions that I hope you can help me to answer.
>
> First of all, about the MPR selection. I read the algorithm described in
> RFC 3626 but when I try it in my lab, it doesn't work as expected (or
> maybe I don't understand it well), for example:
>
> - If set a 4 router network (R1, R2, R3, R4):
>
>                /--R2--\
> R1 --------/          \---------R4
>               \---R3---/
>
> Where *R1 and R4 cannot see each other directly and R2 and R3 are in the
> same place. All routers have the same TX Power. Link Quality is set to 0.*
>
> 1.- The thing is that it doesn't matter which Willingness I set to R2 or
> R3 they are always selected as MPR (except when they have will=0). In
> theory, if R2Will=6 and R3Will=1, shouldn’t be R2 the only MPR? Why to
> choose 2 MPR instead of using only one and minimizing the flooding?
>
> 2.- Another thing I've found with this configuration is about the
> routing. If I try to send a file from R1 to R4, all the data is always
> going through R2 and is only going through R3 when R2Will=0. The routing
> shouldn’t select the route taking into account the Willingness parameter
> as is said in the RFC 3626?:
>
> /           3.2  Several topology entries may be used to select a next hop
>                 R_next_addr for reaching the node R_dest_addr.  When h=1,
>                 ties should be broken such that nodes with highest
>                 willingness and MPR selectors are preferred as next hop./
>
>
> 3.- In another different setup, where all the routers can see each
> other, none of the routers is selected as an MPR, is this normal?
> Shouldn’t be at least one MPR in a OLSR ad-hoc network?
>
>
> Thanks in advance for the answers.
>
>
>

-- 
Ferry Huberts