Mesh networking (XBee/Zigbee)

Hi guys n gals.

I want to set up a mesh network (yes the mesh bit is essential). The application is environmental monitoring to low power consumption is key I can only rely on battery/energy scavenging. I own a bunch of XBee modules (mainly ZB series pro modules) and I’ve had them working well with one coordinator and about 5 end devices. My main problem is that for the meshing to work, the routers and coordinator need to be running all the time, I basically run out of power far too quickly.

So I’ve done a bit of reading RE: Digimesh. I understand that both “routers” and end devices can sleep (plus synchronised sleep is a bonus) and there is no coordinator. However I’m a little confused, do I get some Series 1 modules and flash them with DigiMesh firmware or is there a special Digimesh module?

Has anyone here played with digimesh modules? If they have, how different are they from working with the “normal” XBees?

The Series 2 XBees (ZB) can have “End Devices” sleep. The Coordinator can not sleep as it needs to listen for any “router” or “end device” that ‘wakes’.

If you need any of these to run from batteries then don’t use the high power PRO modules.

Digi Int has info on setting up Sleep. This is what I do with ZigBee modules.

Never used DigiMesh. Check the firmware upgrade options in X-CTU from which modules can run DigiMesh and the Digi Int web site.

I currently use high power pro modules (I need the range) on my end devices which sleep. The problem I’m having is that the coordinator/routers need to be constantly powered and given their power consumption while active, that’s just not feasible (for me).

I think that the series 1 modules support the digimesh firmware, i’d just like to check before buying some and finding out I’m wrong!

yes, series 1 support DigiMesh. The routers in those probably need to be always-on; not sure.

ZigBee ($$$$) has sleeping routers in certain profiles, IIRC.

ZenSyS (Z-Wave products) have sleeping routers (see that forum on homeseer.com)

There’s some public domain C code for meshing (self-forming, self-healing), that uses HopeRF’s RFM2x modules (low cost).

http://www.open.com.au/mikem/arduino/RF22/

well documented. Best I’ve seen.

If your nodes and routers don’t move or move much, it’s easy to use XBees without a PAN coordinator and all nodes use their 64 bit MAC addresses to talk to one another. Easy for you to forward frames if you set the forwarding addresses of neighbors at configuration time, rather than going with a full mesh. This becomes a static mesh, if you will, and is simple to do.

@teevil,

Did you ever flash those Series 1 modules with digimesh? Any luck or hiccups?