Re: [B.A.T.M.A.N.] Node with two wireless interfaces - to bridge them or not?

[elektra]

Hi -

Fragmentation is broken in current Madwifi. Every packet bigger than the 
fragmentation value will not be send. This is bad, because fragmentation 
is pretty important for smooth data transfers.


Another notorious problem is IBSS cell-splitting, you can fix that by using

iwconfig athX ap 02:CA:FF:EE:BA:BE (or whatever cell-id you wish)

Also it is recommended to select the ministrel rate adaption mechanism 
when loading the driver.


Try a recent Madwifi version from  OpenWRT Kamikaze (i.e. get the 
OpenWRT patches and apply them to the Madwifi version used in OpenWRT).


cu elektra

Re: [B.A.T.M.A.N.] Node with two wireless interfaces - to bridge them or not?

[Simon Wunderlich]

Hello Pele,

bridging multiple interfaces is probably not a good idea, because as
soon as you have a cycle there will be bridging loops. The frames will
cycle until they are droppend and there is no TTL to stop them! :)
In Ethernet, a solution for this is STP [1], which will cut off (one of) 
the links in the loop, but probably the good ones, so that is not what 
you want. That is what the mesh is supposed to do. But bridging would
not bring you any performance increase anyway, so i'd suggest to 
stick with your current setup.
(if you want to have only IP per interface for some reason, you can also
have a look at batman-advanced).
To increase multi-hop bandwidth you should better try the standard wifi 
ways to reduce interferences/packet loss. E.g. try to switch off rts, 
switch on fragmentation, limit baserate etc. 

Best regards
Simon

[1] http://de.wikipedia.org/wiki/Spanning_Tree_Protocol

On Wed, Apr 02, 2008 at 11:18:38AM +0200, Predrag Balorda wrote:
 I have one node that has two wireless interfaces. I was thinking to increase
 somewhat the multi-hop bandwidth loss and what is the best way of doing that.
 Currently I have ath0 with two nodes on there and ath1 with another two nodes
 but I'm not bridging those two interfaces. The thing is, they are on the same
 subnet so is there any point in keeping them separate, any performance
 advantage, or should I just make a bridge and add the two ath's to it and just
 have a single IP and run batman on that one bridge or leave it as it is, with
 two IPs from the same subnet and run batman ath0 /w ath1 /w as I do currently?
 
 Pele
 
 ___
 B.A.T.M.A.N mailing list
 b.a.t.m@open-mesh.net
 https://list.open-mesh.net/mm/listinfo/b.a.t.m.a.n


signature.asc
Description: Digital signature