Large wireless network

Hello,

I would like to connect large amount of arduinos to a local server (30 to 200). Each arduino would need only to read a couple of sensors, rtc and log the data to sd card. Everyone one would have it's own power supply.

The most important part would be to be able to transport the arduino and have it retain it's adress on the server. There is no need for sending information from server, except maybe for confirming messages. I was wondering about using wifi shields on all the arduinos to send the data to routers, which would be spread around the building, maybe in every hallway or somewhere where signal coverage would be the best. Is my idea even plausible? What would be the easiest way to test that on smaller scale? Where to look to find examples of server side commands?

Thank you for reading :)

What are you using the network for if all the Arduino's independently log the sensor data to an SD card?

If you want to give each arduino a static IP address then either hardcode it into the sketch before upload or store it in eeprom memory so it survives power down if it's set dynamically using buttons during sketch execution.

There is no need for sending information from server, except maybe for confirming messages.

30 to 200 network enabled Arduinos are likely to swamp your network/server. Might be better for the server to periodically request data from each arduino in turn.

Since you need to buy wifi shield for each and everyone, isn't better solution to go with raspberry pi ? He has ethernet on him self ?

Riva: What are you using the network for if all the Arduino's independently log the sensor data to an SD card?

If you want to give each arduino a static IP address then either hardcode it into the sketch before upload or store it in eeprom memory so it survives power down if it's set dynamically using buttons during sketch execution.

There is no need for sending information from server, except maybe for confirming messages.

30 to 200 network enabled Arduinos are likely to swamp your network/server. Might be better for the server to periodically request data from each arduino in turn.

I would mainly monitor temperature in portable coolers, loging is just for documentation, to confirm that the cooler was on right temperature all the time, and server would be used to see current information on all the sensors, and if one overheats inform someone.

I've given this much more tought after asking the question, and I was thinking of sending data every minute but requesting data would definitivly make it easier to handle the data on the server side.

milorad: Since you need to buy wifi shield for each and everyone, isn't better solution to go with raspberry pi ? He has ethernet on him self ?

I've never used raspberry, but I could try. Money is not a big problem if it is much simpler, I only need to do the small scale model and show it working, and then I might get funding for the bigger version.

Now my biggest concern is "is it possible?", can I connect hundreds of arduinos/raspberrys on single wifi network, and have one of them connected to the pc and do the server side?