There is disclosed, for use in a CDMA wireless network, a partitioned selection and distribution unit (SDU). The partitioned SDU comprises a first controller located in at least one base station of the CDMA wireless network for performing radio dependent functions, wherein the radio dependent functions are related to the transfer of wireless traffic between base stations and mobile stations in the CDMA wireless network. The partitioned SDU also comprises a second controller located in the mobile switching center of the CDMA wireless network for performing radio independent functions, wherein the radio independent functions are related to the transfer of voice traffic, data traffic, and/or signaling traffic between the CDMA wireless network and a wired network coupled to the CDMA wireless network.