One of the largest problems in wireless communication is cell phone security. There are two worries: Other people listening into cell phone calls and other people illegally billing time to a user's account. The latter is called cell phone cloning. Cell phone cloning is illegal and if you suspect you are a victim of cell phone cloning, notify your cell phone carrier immediately.

Unfortunately, analog cell phones transmit in plain FM, and provide no cell phone security. For instance, a few years ago, Newt Gingrich had a cell phone conversation taped by someone using a simple police scanner, which is designed to receive police activity on the CB frequencies. Since analog phones have such weak cell phone security, the architects of digital technology designed digital phones with much more robust security. 

Digital phones employ encryption to secure the phone and the conversation. Encryption is used to make sure that it is almost impossible to "latch" onto a conversation. The digital phone encryption works by picking a key that is used in an equation that compresses the audio. The encrypted key is sent to the cell tower so the cell tower knows how to decode the conversation. Therefore, even if the person with the scanner finds the channel and time slice you are using, they would need to find the encryption code to make sense of the signal. Cell phones also must be protected from cell phone cloning. By encrypting the cell phone number and related information when sending the information to the switch, cell phone cloning is prevented.