Consumers are demanding world-wide cellular access to the internet. This requires a global standard and effective means of accessing the internet from wireless devices. The IMT-2000 project attempted to fix the first problem by harmonizing all wireless interfaces into one global standard. However, this attempt failed and a new family of standards was issued. In response, Operator Harmonization Group (OHG) is currently harmonizing two of the most popular CDMA standards: WCDMA and cdma2000. One major issue holding back complete harmonization is mobility management. WCDMA is used in Global System for Mobile Communications (GSM) systems where general packet radio service/enhanced data for GSM evolution (GPRS/EDGE) protocols are currently being developed to act as the mobility manager. Cdma2000 is designed for IS-95 and currently uses Mobile IP as its mobility manager. If one global standard is to be achieved, the same mobility management system has to be used by both WCDMA and cdma2000. The second problem deals with providing reliable access over unreliable wireless links. In this paper, a conceptual model integrating GSM and TCP/IP using Mobile IP as the mobility manager is presented. This model presents a method to implementing Mobile IP over a GSM cellular network. The conceptual model also provides a solution to deploying TCP over wireless links. This model can serve as a useful starting place to harmonizing one global 3G standard.