OpenBTS

OpenBTS is a type of software that allows people to make phone calls over the internet. It works by creating a virtual cell phone tower that other devices can connect to in order to make calls. With this software, people can make phone calls over the internet even if they don't have a traditional phone line. It works just like a normal phone tower, but instead of being connected to the big phone network run by the phone companies, it is connected to the internet.