The second generation of wireless networks designed to improve on analog with digital circuit-switched solutions. The three main 2G technology standards are Global System for Mobile Communications (GSM), which is based on European Telecommunications Standards Institute (ETSI) standards, time division multiple access (TDMA) IS-136 and code division multiple access (CDMA). The Japanese personal digital cellular (PDC) standard was similar to IS-136. GSM and IS-136 are TDMA technologies. 2G services typically support data rates of 9.6 Kbps, 14.4 Kbps and up to 64 Kbps in certain IS-95B deployments.