[B.A.T.M.A.N.] where is batman-adv on multicast? specifically IPTV

[B.A.T.M.A.N.] where is batman-adv on multicast? specifically IPTV

[dan]

you may have seen my other posts about wISP service for batman-adv.
I'm looking at how batman-adv can handle multicast

the design is batman-adv running over PtP wireless links and then PtMP
access radios bridged in.

I'm looking at the multicast-optimizations page but I'm unclear on something.

I see that if there is just one listener, then it basically becomes a
unicast stream.  But what if I have multiple sites (lets say 10) and
at 2 sites there are 1 listener each.

does this mean that all 10 sites will get the broadcast? or that just
the 2 sites that have listeners will get the broadcast?

I'm not sure how old that page is or if anything has evolved.

The goal here would be to only send a stream to a site if there were
at least 1 listener.

I could also potentially have a device at each site handling PIM for
multicast, but I haven't dived into how that would work on batman-adv
or if I'd have to run a separaet VLAN between each PIM router outside
of batman-adv.

Re: [B.A.T.M.A.N.] where is batman-adv on multicast? specifically IPTV

[Linus Lüssing]

Hi Dan,

On Sat, May 26, 2018 at 07:43:03PM -0600, dan wrote:
[...]
> I see that if there is just one listener, then it basically becomes a
> unicast stream.  But what if I have multiple sites (lets say 10) and
> at 2 sites there are 1 listener each.
> 
> does this mean that all 10 sites will get the broadcast? or that just
> the 2 sites that have listeners will get the broadcast?

Currently, if 2 (or more) batman-adv nodes have 1 listener each (for
the same multicast group) then the packet will be flooded. Meaning all
nodes in the mesh will receive it.

I currently have two more patches for batman-adv open for further
testing to allow not just multicast-to-unicast conversion to a
single destination, but a multicast-to-multi-unicast conversion, too.
They are currently burried in here:

https://github.com/freifunk-gluon/gluon/pull/1357

If you are interested and brave enough to try them then let me
know how that goes for you :-).

Regards, Linus

Re: [B.A.T.M.A.N.] where is batman-adv on multicast? specifically IPTV

[dan]

I'm not brave enough to test :)  I'm still evaluating batman-adv for
this deployment model and haven't even setup real hardware to test
yet.  I think that I can live with a separate VLAN and PIM multicast
routing if need be plus I'd probably be running whichever batman-adv
version is in-kernel on ubuntu so that upgrades are more seamless so I
would imagine quite a long time until these patches make it in.

On Sun, May 27, 2018 at 4:08 PM, Linus Lüssing <linus.luessing@c0d3.blue> wrote:
> Hi Dan,
>
> On Sat, May 26, 2018 at 07:43:03PM -0600, dan wrote:
> [...]
>> I see that if there is just one listener, then it basically becomes a
>> unicast stream.  But what if I have multiple sites (lets say 10) and
>> at 2 sites there are 1 listener each.
>>
>> does this mean that all 10 sites will get the broadcast? or that just
>> the 2 sites that have listeners will get the broadcast?
>
> Currently, if 2 (or more) batman-adv nodes have 1 listener each (for
> the same multicast group) then the packet will be flooded. Meaning all
> nodes in the mesh will receive it.
>
> I currently have two more patches for batman-adv open for further
> testing to allow not just multicast-to-unicast conversion to a
> single destination, but a multicast-to-multi-unicast conversion, too.
> They are currently burried in here:
>
> https://github.com/freifunk-gluon/gluon/pull/1357
>
> If you are interested and brave enough to try them then let me
> know how that goes for you :-).
>
> Regards, Linus