In the age of IoT, a mobile device is equipped with sensors and intelligence, in a heterogeneous architecture. Before providing this information, it is likely that PLS will also be influenced by other areas  such as physical security or biometrics . Perhaps crKG and RF-Fingerprinting  techniques may be revolutionary for key exchange and authentication problems, but they still have limited and contradictory performance, as reported in the current literature. For example, in  1 minute is required to generate 128-bit security keys, while in  only 16 ms is theoretically estimated for 256-bit security keys. S. Jana, S. N. Premnath, M. Clark, S. K. Kasera, N.
Patwari, S. V. Krishnamurthy, in Proc. 15th Annu. Int. Conf. The crowd. Calculation.
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doi.org/10.1109/TWC.2008.070194. There is already evidence that the frequency range offers greater power and flexibility for PLS: in , alice and Bob will receive a key generation of 90 bits per packet with only 5∼ of the key gap, while about tens of bits per second are generated by RSSI methods. Authentication: Alice and Bob must trust each other before performing CRCGs. This prelude could be achieved in the traditional way , for example by using secret keys stored by the device manufacturer and Challenge Response authentication methods. There are also PLS techniques such as PUF , Vicinity-Solution  or radio signature authentication [85, 88, 89]. RF Fingerprinting can be implemented today with good results [60, 90-95], thanks to the power of machine classification and aggregation and deep learning [96-98]. At this point, Eve can try to play as bob or Alice, and play a man-in-the-middle attack. Authentication is not part of this work….