On Wed, 2007-02-21 at 09:04 +0900, giuseppe de marco wrote:
> Suppose we want to update the routing module (OLSR) with a modified 
> version of it, or also
> we want to change the parameters in all OLSR modules running inside the 
> nodes of an ad-hoc net.
> 
> How we can handle it automatically?

- Deploy the new version
- update the config files: Changes in most variables are relatively uncritical
   - one can never rule out the possibility of (short-time) routing loops.
   The only critical thing is that "LinkQualityLevel" must be either "0" on all
   or no nodes (and "UseHysteresis" must have also the correct value since these
   are incompatible).
  Folks, please correct me if there is something important missing!
- restart the daemon 

> I think OLSR should maintain a state variable which indicate the 
> consistency with respect to all others nodes.

Well, one doesn't want such a state variable (because of the reasons
below)and that was the historical reason to develop the concept of a
"protocol" where you can change everything as long as the protocol
didn't change.

> If the consistency is perfect then we can use the new 
> downloaded/uploaded version, Otherwise we must wait....but until when?

> The consistency means that every node runs the same OLSR version with 
> the same configuration parameters.

FunkFeuer has AFAIK an unknown number of OLSRD versions (from the last
several years) in parallel (because it is a lot of work to update the
firmware on dozens of nodes so it is at most done if someone fixes a
problem there and the one is fed up with the old version) in the mesh
(with "LinkQualityLevel 2" - it is much better in larger nets) and it
works ATM.

> Does anyone implemented a technique to handle this problem?

Personally I'm not fond of: updating software automatically on a net of
(more or less) independent nodes run/managed by different people.
<paranoid>I wouldn't allow something on my nodes (unless I'm in control
of it).</paranoid>

	Bernd
-- 
Firmix Software GmbH                   http://www.firmix.at/
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