Hi Berat,
yes this is expected: * the first Ethernet section is required for WiFi (or Ethernet) to send the packet on the physical link between two neighbors - this will change with every hop taken in the mesh * The batman section includes a couple of control fields and also source and destination (at least for unicast packets). These sources and destinations are for the originators, that is mesh nodes within the mesh, which may be a couple of hops away * Finally, the second Ethernet section contains source and destination of the devices which are actually talking to - these devices are not necessarily mesh nodes, but might be devices only bridge into the batman-adv mesh network. batman-adv takes these Ethernet frames as they are and encapsulates them by adding its own batman section and the per-hop first ethernet section as you saw.
So if you want to work on the "originator" layer, have a look at the batman section source/destinations.
Cheers, Simon
On Wednesday 22 July 2015 16:59:37 Berat wrote:
Hi,
I was trying to understand how batman-adv encapsulates ethernet frames. Batman dissector of wireshark, shows an ethernet II section, then a batman section, then again an ethernet II section. Is this rappresentation respects the original capsulated header format? I couldn't find a scheme that shows fields of an encapsulated header in the documentation. So with wireshark, it tells me something like that:
Dst.Mac|Src.Mac|Type|Packt Type|Version|TTL|Seq.No|Dst.Mac|Src.Mac|Type
___________________/____________________________/__________________/ First Ethernet Batman Section Second Ethernet II Section II Section
Why there are two times destination and source mac addresses? I want to retrieve mac addresses of originators of packets by working on raw packet data. But i'm a little bit confused with this scheme. Sorry if it's a banal question, i don't have much experience with networking. Thanks for any help.