Hi there,
In case I want to deploy a "product" that uses two moteinos "per home", would they interfere with neighbouring homes ?
If my neighbour has one product (or several neighbours on a condo apartment), would this setup work ?
I guess there would be the need to add some software verification to avoid neighbouring devices from collecting data from other devices.
Cheers!
If you use the out-of-box library then all will talk on the same frequency (whatever you choose). BUT at 2 nodes per home it will not be a lot, assuming you are not streaming a lot of data. Either way the library has a mechanism where it listens before it talks. So each node will listen to its channel and only talk when the channel is "free". That drastically reduces chances for collisions/interference.
There is also the NETWORK ID, NODE ID and don't forget encryption. All those parameters allow you to separate the different "homes" or networks of nodes. I would either set each home to a different encryption key, or set them to a different network ID, or both. If you want to be able to step in and listen promiscuously to all the nodes on all the networks (say you come on the stair case of the building or walk on the street and need to debug your deployments or something ...) then set them all to different networks, but keep the same encryption key. Then with your DEBUG node you come and listen to everyone by toggling:
void promiscuous(bool onOff=true);
Is this making sense?
Thanks Felix, that makes sense.
My scenario is this: I have one of more moteinos with RFID's sensors that control door access (imagine that these doors have different access level restrictions).
When a user waves his card, the moteino at the door would ask the central gateway if that particular card id is authorised to open that door. If affirmative, the gateway records this data and sends a "Open Door" to the moteino at the door.
I am wondering if this might be a problem given the delay that will happen between "waving" the card and then waiting for the answer (maybe 2 to 3 seconds tops ?). If I have multiple doors for instance, that would increase the possible collision.
Does my concern makes sense ?
Thanks again,
The delays will be on the order of tens of milliseconds at most. A short packet will take a few ms to send and a few more to ACK if you use ACKs. Then it's up to you how much you spend at the gateway to validate etc. Seconds sounds too long.
Thanks! I will test as soon as I get my hands on two of these guys :)