ISM band
The ad hoc networking technology operating on Wi-Fi ad hoc mode, at the unlicensed ISM band of 2.4 GHz may result in profit loss by cellular carriers since ISM band is free and unlicensed while cellular carriers operate on licensed band at 900 MHz, 1200 MHz, 1800 MHz, etc. This has the potential to threaten telecommunication operators (telcos). Smart phone mobile ad hoc networks can operate independently and allow communications among smart phones users without the need for any 3G or 4G LTE signals to be present. Wi-Fi ad hoc mode was first implemented on Lucent WaveLAN 802.11a/b on laptop computers. Since Wi-Fi is present and embedded in all smart phones today, this earlier technology was adapted for smartphones.