Batman adv selective broadcast mechanism

Batman adv selective broadcast mechanism

[oytunyapar]

Hi everybody,

    As I check, batman-adv protocol, sends IP broadcast packets, to every slave interface, including the slave interface from which the broadcast packet is received. Is there any way for preventing the batman-adv from sending IP broadcast packets to some of the slave interfaces (etc. the one which the packet is received)?

Regards.
Oytun

Re: Batman adv selective broadcast mechanism

[Linus Lüssing]

Hi,

On Wed, Mar 24, 2021 at 12:16:16PM -0000, oytunyapar@hotmail.com wrote:
> Hi everybody,
> 
>     As I check, batman-adv protocol, sends IP broadcast packets, to every slave interface, including the slave interface from which the broadcast packet is received. Is there any way for preventing the batman-adv from sending IP broadcast packets to some of the slave interfaces (etc. the one which the packet is received)?

When there is just a single neighbor on the interface a node
received the packet on that batman-adv avoids sending it
back automatically. E.g. this case here:

https://www.open-mesh.org/projects/batman-adv/wiki/Broadcast#IIII-Single-Neighbor-Is-Previous-Sender

If there are multiple neighbors on the receiving interface then
batman-adv assumes that other neighbors might potentially not have
received the packet from the original sender. And will therefore
rebroadcast on the incoming interface, too.

If you are 100% sure that all other neighbors received it from
the original sender then there is this old patch which isn't
upstream though (including the discussion with why it was
rejetected for upstream):

https://patchwork.open-mesh.org/project/b.a.t.m.a.n./patch/1380030033-11533-1-git-send-email-linus.luessing@web.de/

Regards, Linus

Re: Batman adv selective broadcast mechanism

[oytunyapar]

Hi Linus,

    Thank you for the answer. Configuring batman-adv from /sys is deprecated in the last version (batctl is the only way now). I am not sure how to apply this patch. What do you suggest as a proper way of doing this?

Regards.
Oytun

Re: Batman adv selective broadcast mechanism

[Linus Lüssing]

Hi Oytun,

Are you able to recompile the kernel module and batctl? If so, I
could have a look at updating that patch for a more recent
batman-adv version.

Actually, I'm also kind of curious about your use-case. Sounds
like it's not 802.11 wifi you are using, right?

Regards, Linus


On Thu, Mar 25, 2021 at 12:58:15PM -0000, oytunyapar@hotmail.com wrote:
> Hi Linus,
> 
>     Thank you for the answer. Configuring batman-adv from /sys is deprecated in the last version (batctl is the only way now). I am not sure how to apply this patch. What do you suggest as a proper way of doing this?
> 
> Regards.
> Oytun

Re: Batman adv selective broadcast mechanism

[oytunyapar]

Hi Linus,

    I hard coded it, instead of making a configuration. We could use with this way.
    You are correct Linus, it's not 802.11 wifi. We are using MARLIN protocol (NATO STANAG-4691).
    This protocol aims for gaining TCP/IP features to HF and UHF radios.
    We are using BATMAN protocol, for inter-MARLIN network routing. MARLIN itself has features for handling routing, internally, for a single  MARLIN network.

Regards.
Oytun