Study of the impact of information protection on the volumes of data packets of Internet of Things protocols

Abstract

The article discusses the problem of increasing traffic volumes due to the use of encryption. Data packets of Wi-Fi, Bluetooth, 6LoWPAN standards, as well as ZigBee, WirelessHART and NB-IoT protocols were selected for analysis. It was determined which parts of the packet are encrypted and which algorithms are used for this. Wi-Fi, Bluetooth, ZigBee, 6LoWPAN and WirelessHART use the AES algorithm with a 128-bit key, while NB-IoT uses 128-EEA2 with the same key size. Both algorithms (AES and 128-EEA2) require the data to be a multiple of the key size, so a bit sequence is added to the payload to achieve the desired size. This increases the total size of the packet being transmitted. A study of this effect was carried out, and graphs were made showing the dependence of the amount of addition on the amount of useful data. The graphs have a sawtooth shape due to the fact that at certain volumes of useful data, the addition reaches its maximum value. The average volumes of additions for each standard were also calculated: Wi-Fi - 2.13%, Bluetooth - 10.64%, ZigBee - 24.81%, 6LoWPAN - 23.22%, WirelessHART - 23.08%, NB-IoT - 25.96%. The average values ​​of add-ons for packets up to 64 bytes were studied separately: Wi-Fi - 9.95%, Bluetooth - 16.31%, ZigBee - 8.00%, 6LoWPAN - 11.55%, WirelessHART - 10.12%, NB-IoT - 20.21%. In the absence of restrictions on the size of useful data, the best result was shown by the Wi-Fi standard, and the worst by NB-IoT. In cases with limited payload size, ZigBee performed best and NB-IoT performed worst