Moving on to radio/wireless communication, our DVR does not have much going on with regards to radio communication other than the data that transports to the DVR from client applications or cameras. Most IoT devices and environments have several different radio communications broadcasting on different frequencies using different protocols. Luckily, we only have to worry about Wi-Fi and cell provider entry points into the DVR.
For our radio communication threat modeling exercise, we can simply update previously drawn diagrams to reflect the radio communication that occurs within devices and applications.
An example architecture overview for radio communication usage within the DVR system is illustrated as follows:

As you may be able to tell, the wireless communication is limited to users accessing the DVR via client devices such as a browser and applications as well as wireless-enabled...