Purpose and Scope This standard specifies Data-Service Control (DSC) for TDMA wire4 less systems. DSC uses standardized user-network commands and responses to access the following services and features:Async Data Service (ADS) provides async data service between wireless and PSTN (Public Switched Telephone Network) users. It uses circuit-mode access over the radio interface and modem-based connections into the PSTN.Direct Async Data Service (DADS) provides async data service between wireless users and PDN (Packet Data Network) users or ISDN (Integrated Services Digital Network) users. It uses circuit-mode access over the radio interface and direct-digital connections into PDNs or the ISDN. Note that PDNs include the internet.Fax Service provides fax service between wireless and PSTN users. It uses circuit-mode access over the radio interface.General User Datagram Protocol Transport Service (GUTS) provides data services between wireless users and a teleservice server. It uses packet-mode access over the radio interface and direct-digital connections into the teleservice server.Short-Message Service (SMS) provides short-message services between wireless users and a message center. It uses packet mode access over the radio interface and direct-digital connections into the message center.Autodial Feature provides methods for DTE (Data Terminal Equipment) to autodial voice calls.EGPRS-136 provides packet-data service between wireless users and PDN (Packet Data Network) users or ISDN (Integrated Services Digital Network) users. It uses packet-mode access over the radio interface. See TIA/EIA-136-351 for the specification of commands and responses used for this service.A mobile termination provides access to these services and features via a data port. DSC requires an underlying link protocol as specified ed in TIA-136-310 [10]. It also requires cellular call control, datagram control, short message control, and other cellular functions, as specified in other parts of TIA-136 [9]. To aid the reader, §§ 2 and 3 contain descriptive information: § 2 pro6 vides an overview, § 3 describes DSC's structure. §§ 4 and 5 contain requirements: § 4 specifies signals, § 5 specifies processes. References appear in § 6. Finally, Annex A provides guidelines to application programmers, and Annex B lists and defines acronyms. Note that § 5 refers to figures too large to fit within the body of the standard. These figures are enclosed in a separate envelope. Readers will find the following documents helpful in understanding this standard: X.200 [6] and Z.100 [7]. Similar to X.200, this standard uses reference models to organize concepts and requirements into a logical structure. These reference models are not meant to unnecessarily constrain implementations - any implementation that, as a whole, behaves the same as DSC specified in this standard, by definition, complies with this standard. If the requirements of this standard conflict with the requirements of referenced standards, this standard shall govern.