Simple sensor network architecture?

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Anonymous
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I'm slowly diving in to the world of BLE. The BLE pioneer kit and the examples have been very helpful and I was able to generate my own custom device/profile.

   

The end goal is to have a a number of BLE sensors that all connect to a single "central".

   

- Data rate: very low (2-4 bytes/minute) from each sensor

   

- Battery life: important but not critical. 

   

- Security: Some basic security, so that data can't be read just by any smartphone. But don't need anything advanced, none of the data is sensitive.

   

- Number of sensors: 10 to 20

   

 

   

The question is: How do I architecture this?

   

Do my sensors send notifications or indications?

   

Should sensors wake up on 1min interval and waits for connection, while the "central" is scanning for devices? Then "central" connects securely, reads data and the slave goes back to sleep?

   

How do I implement basic security? Should sensors have the "central" added to the white-list (hard-coded)?

   

 

   

Thank you,

   

Boris.

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1 Solution
Anonymous
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Hi Boris,

   

Seems like you are trying to implement something like a Mesh. Please note that we can simultaneously maintain connection with only one device at a time, so it should be implemented in a TDM central topology. The data can be sent as notifications. Have a look at these projects:

   

https://github.com/cypresssemiconductorco/PSoC-4-BLE/tree/master/100_Projects_in_100_Days/Day030_Tim...

   

https://github.com/cypresssemiconductorco/PSoC-4-BLE/tree/master/100_Projects_in_100_Days/Day049_BLE...

   

https://github.com/cypresssemiconductorco/PSoC-4-BLE/tree/master/100_Projects_in_100_Days/Project052...

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1 Reply
Anonymous
Not applicable

Hi Boris,

   

Seems like you are trying to implement something like a Mesh. Please note that we can simultaneously maintain connection with only one device at a time, so it should be implemented in a TDM central topology. The data can be sent as notifications. Have a look at these projects:

   

https://github.com/cypresssemiconductorco/PSoC-4-BLE/tree/master/100_Projects_in_100_Days/Day030_Tim...

   

https://github.com/cypresssemiconductorco/PSoC-4-BLE/tree/master/100_Projects_in_100_Days/Day049_BLE...

   

https://github.com/cypresssemiconductorco/PSoC-4-BLE/tree/master/100_Projects_in_100_Days/Project052...

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