Hello,

Another comment on your scenario: Each node should always be reachable (if a suitable path in the mesh exists) via the IP of the first configured interface ( eth0 if launched as: batmand eth0 ath0 ).

Some more background: If batman is configured to serve multiple interfaces only one of them (the first defined one) is announced with a TTL=50. The second and further interfaces are by default announced with a TTL=2 only. The reason for that is, that one known IP-address is sufficient for distant nodes to reach that node and therefore at least one of the configured interfaces and corresponding IP must be announced with a high (50) TTL. Announcing all interfaces with a high TTL would only cause increased routing tables and a waste of bandwidth due to additional OGM messages traversing the mesh. However, all configured interfaces need to announce their existence at least to their neighbors in order to indicate the existence of a link so that they can be used (thats why the remaining interfaces are configured with a TTL=2 ). Because all IPs are announced (with seperate OGMs) via all interfaces, it does not matter which interfaces have a good connectivity to its' neighbors and which not. That is one interesting thing with batman: A node does not know the exact path to a destination node, it only knows the best neighbor towards the destination node. Therefore, in a multi-hop-scenario, you can even configure intermediate nodes with a TTL=2 for all interfaces, making such nodes fully invisible for all more-than-two-hops-away-nodes. Such invisible intermediate nodes would still be used for routing end2end traffic.

ciao, axel

On Wednesday, 14. February 2007 13:37, Benjamin Henrion wrote:

Hi,

We met with several people in Brussels active on the reseaucitoyen project to test Batman.

Our configuration was 4 laptops like this:

laptop1 <----ethernet----> laptop2

•                                           +
  

•                                           +
  

•                                           +
  

wlan1 wlan11

•                                           +
  

•                                           +
  

•                                           +
  

laptop3 <----ethernet----> laptop4

With 8 different IPs for the 8 interfaces.

We launched batman-0.10 on all the nodes, but it appeared that one of the interfaces was not reachable via ping. And the experience was reproductible when we restarted the dameon, sometimes with a different IP unreachable.

We are going to test the same configuration soon to see if batman chooses the fastest route in terms of throughput.

Best,

-- Benjamin Henrion <bhenrion at ffii.org> FFII Brussels - +32-484-566109 - +32-2-4148403 _______________________________________________ B.A.T.M.A.N mailing list B.A.T.M.A.N@open-mesh.net https://list.open-mesh.net/mm/listinfo/b.a.t.m.a.n