16 DN Limit?

Some where in the videos and documents I recall hearing mentioned a limit or perhaps a suggestion that a chain of 16 DNs was as far as you could/should go from one POP. I can’t find this anymore and now have all sorts of design questions.
I assume it is due to performance declining the further you go, but if I have clients that are looking for pogo bandwidth as opposed high performance this might be an acceptable trade-off.
Would it be reasonable to set up 16DNs-> POP ← 16DNs ie 16 from each sector ?
What about POP->10DNs then fork to two strings of 6DNs ?
What about POP->10DNs then fork to four strings of 3DNs ?

I’m not sure about the 16 DN limit. Each hop has 600 microseconds latency, so there will be very little performance decrease going that far away from a POP. Normally, designs are not completely linear. Usually, operators will design the DN’s so they form a ring or maybe a couple of rings in a market. The recommendation for the polarities to work out correctly is to have an even number of DN’s in each ring. If you have an odd number, then one link will have to be hybrid even or hybrid odd, which as 1/2 the capacity of even or odd.

The only limitation that I’m aware of is that you can only mesh 2 DN’s per sector, and then you can connect 13 CN’s maximum to a sector that has 2 DN’s meshed to it.

The other limitiation is that an onboard E2E controller can only support 31 devices maximum. The External E2E controller can support up to 500 devices. The /56 seed prefix means that SLAAC can address 256 /64 devices, so if you need more than 256 devices, you can configure the seed prefix to /48 for example, and then can address 65000 devices.

In my experience so far, the possible DN locations determine what the topology looks like. In mnay networks, there are groups of DN’s meshed, with a PTP or v3000 link to join up another group of DN’s using relay mode on the connecting link.

Hope this helps.

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It’s 15 hops away from the PoP, and this has to do with Open/R Layer 3 Routing more than the physical limitations of the Cambium Networks device.

You might find something here; GitHub - facebook/openr: Distributed platform for building autonomic network functions.

If not please see this slide;

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@James_Mifsud gritty detail question … is this wireless hops only or does a wired connection from a v3000 to a v5000 count as a hop as well ?
I am looking at a place where I could close a ring of 15 wireless hops but there are five extended distance hops that are enabled by use of v2000 or v3000 connected to a v5000 by ethernet