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.
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
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
b.a.t.m.a.n@lists.open-mesh.org
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dan -
Linus Lüssing