- When you are making a call and your privacy is protected, others cannot use cell phones or any other equipment to listen to your telephone call. Privacy is especially important, for example, when you are using your phone to make credit card purchases.
- Cell phones have different ways to let you know if your call is protected or not. For example, when connecting to a call, your cell phone may give one tone to indicate that privacy is protected. It may give another tone to indicate your privacy is not protected. Some phones will use just one tone, but the phone would beep once to indicate protection and twice to indicate that no protection is in place.
- In order to interpret the tone or tones you get when you make a call, look in your phone's instruction manual under "Privacy Tone." You can also look up your cell phone carrier online and search for the manual, or you can call the toll-free telephone number for your cell phone service carrier. Once you find out how to interpret the tone, you will know whether your privacy is protected when you make a call.
- Your cell phone has a basic level of encryption to keep others from hearing your call. A second level of encryption, a spread spectrum technology known as Code Division Multiple Access ("cdmaone" or "CDMA2000"), provides you privacy while roaming. This function breaks the data into bits and pieces as it is sent from one caller to another. The privacy tone indicates whether this second layer of security is active.
- CDMA200 or cdmaone spread spectrum technology has been used for military communication encryption since the late 1950s. Its use for personal cell phone technology was made available in the 1980s. Before digital technology was used for cell phones, analog technology was used, which is much less secure than digital technology.