[Olsr-users] AHCP [was: OLSR Pro Active autoconfig news?]

Roar Bjørgum Rotvik (spam-protected)
Tue Dec 18 10:48:32 CET 2007

Juliusz Chroboczek wrote:
>> I'd need a solution for assigning IP adresses automatically
> AHCP was carefully designed to be independent of the routing protocol:
> it has its own flooding mechanism that doesn't rely on IP routing.

How does this flooding mechanism work?

> A different approach is to embed an autoconfiguration protocol within
> the routing protocol, which is what Roar's ``PAA'' does.

Not quite so :) PAA is not embedded in the routing protocol. It just happens to use the 
olsr flooding mechanism, but there is nothing stopping PAA (apart from implementing it) 
from using it's own flooding mechanism.

But as olsr has MPR (optimized flooding) and olsr was used in our ad hoc network, this was 
a perfect match.
Now today everyone has more experience with standard olsr and the negative sides, but that 
is another issue..

> Note that duplicate detection is not reliable in any case: the mesh is
> not necessarily connected at the time a node's interface is configured,
> and hence a duplicate can happen even though DAD has been performed at
> configuration time.  The solution would be to make the autoconf protocol
> listen throughout the node's life, and add some election mechanism to
> resolve duplicates when they happen.  An interesting problem, but not
> one that I'm going to tackle right now.

Yes, PAA will use DAD during first IP address allocation. Merging of separate ad hoc nets 
will probably lead to address collitions that needs to be handled. I don't think this is 
solved in PAA today (some years since I worked with PAA, so I don't remember all the details).

Roar Bjørgum Rotvik

More information about the Olsr-users mailing list