Cellular network

Within the United States, different types of digital cellular networks abound that follow distinct incompatible sets of standards. The two most dominant types of digital cellular networks are known as Code Division Multiple Access (CDMA) and Global System for Mobile Communications (GSM) networks. Other common cellular networks include Time Division Multiple Access (TDMA) and Integrated Digital Enhanced Network (iDEN). IDEN networks use a proprietary protocol designed by Motorola, while the others follow standardized open protocols. A digital version of the original analog standard for cellular phone service, called Digital Advanced Mobile Phone Service (D-AMPS), also exist.