During the last months I spent some hours in the specifications of EnOcean telegrams. These telegrams are used in domain of home automation. The EnOcean Alliance publishes all necessary specification on their website. One of the relevant specifications is EnOcean Serial Protocol 3 (ESP3). In this description you can find all information to understand the protocol used by EnOcean.The specification of this protocol is also standardized and published as ISO/IEC 14543-3-10.
If you are interested in collecting telegrams to analyze them and to understand the protocol behind them, the following project may be interesting for you: EnOceanSpy. I’ve hosted this small piece of software on GitHub. It’s written in C and there is a binary version available for Raspberry Pi (RasPi). On this way you can use your RasPi in combination with an USB300 stick. The following photo demonstrates a buildup including a WakaWaka as power source.
EnOcean allows on the one hand one-way and on the other hand bidirectional communication between devices. Currently most of this communication is not decrypted, so you can read all information communicated via air. There is a first specification to use cryptography for EnOcean protocol. I will give you an overview on this way of encryption in the next time.
Have fun to seek your environment after EnOcean devices :)