Re: [B.A.T.M.A.N.] What routingprotocol is similar to B.A.T.M.A.N ?

[elektra <onelektra@gmx.net>]

Hello Michael -


this question frequently pops up on this list.

You can use layer 3 Batman to announce a default route, but this is not 
recommended. Default routes in a large mesh are a pain in the ****. 
Which is something we quickly realized in the Freifunk community as soon 
as we had more than one gateway or malfunctioning gateways  - those will 
act as black holes and effectively interrupt your service.

You can circumvent the 0.0.0.0/0 check in Batman, by announcing two 
HNA's of 0.0.0.0/1 and 128.0.0.0/1 with the -a option. If you don't 
define a gateway class on the gateway the Batman gateway clients can't 
select a gateway.

Disadvantages: Other than the fact that I personally consider the 
announcement of 0.0.0.0/0 routes as sabotage - none that I know of, 
really. A few bytes overhead in the OGMs of the gateway, thats it.

We have occasional OLSR advertisement fade-ins on this list - I guess 
the Babel/OLSR/Batman quarrel will become proverbial one day ;-)

Cheers,
Elektra