Configuring an XBee-ZB router as an end device with SM

I haven’t worked much with end devices, but have started a project with one now. I was going to load the End Device API firmware, but I noticed that Sleep Mode (SM) can be set in the Router API firmware (see attached XCTU screen snap).

I set SM to 1 (pin sleep) and everything seems to work as expected. But this has left me wondering why End Device firmware exists at all. I’ll try the End Device firmware just to see if I notice any difference, but I’m wondering whether anyone else has come across this or has ideas.

When a router has SM=1, the NC (Number of Remaining Children) is set to 0, so that is the same as an end device.

But this has left me wondering why End Device firmware exists at all.

Sometimes you don't want some XBees acting as routers. Those on the edge of a network don't contribute when acting as routers, since they have no one to route messages to.

PaulS: Sometimes you don't want some XBees acting as routers. Those on the edge of a network don't contribute when acting as routers, since they have no one to route messages to.

My assumption, and it is only an assumption, is that a router so configured wouldn't actually be routing traffic. There'd be little point in it, since it's sleeping most of the time.