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+[Encoder receiver transmitter](https://en.wikipedia.org/wiki/Encoder_receiver_transmitter) (ERT) is a packet radio protocol developed by Itron for automatic meter reading. The system uses OOK short range radio which is transmitted in the unlicensed 900-920 MHz band, so that meters can be read from a passing vehicle. This is mainly used in USA. 
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+The data is not encrypted, and does not have functions to enable full control. The system is not as advanced as a smart meter and lacks the control or  security in the data transfered.
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