With the ever evolving mobile cellular technology, more standards are being defined and upgraded with the goal to provide better quality of service as well as higher capacity. This paper focuses on the performance of the Mobile/Wireless network interface for IS-136, a North-American standard for digital cellular systems. There is no doubt that voice service can be affordable but how does the interface react to the addition of Short Message Service (SMS) is still under investigation. A study of the reverse access control protocol of IS-136 Digital Control Channel (DCCH) is provided and performance results are presented taking into consideration different setups for the access control parameters and support for SMS. Finally, guidelines are provided on how to set-up the system. © 1999 IEEE.