Abstract—This paper focuses on the compliance of publicly
available specifications of Global System for Mobile communication
(GSM) with the extremely closed GSM industry with the
help of RTL-SDR, GNU Radio and Wireshark. GNU Radio is a
free and open software which enables the translation of realworld
systems to programmable flow graphs. GSM, together
with other technologies, is part of the evolution of wireless
mobile telecommunications. Hence, verification of GSM working
is of crucial importance. During this paper, Control channel
information like the bandwidth for specific network providers
was reckoned, along with the IMSI number and ARFCN channel
in use by mobile device of the respective network.