Today's telecommunication infrastructure includes widely varying technologies: The Internet, PSTN, Cellular-Telephony, Pagers etc. The ICEBERG (Internet Cellular BEyond the thiRd Generation) project envisions the integration of these technologies. In particular, we are interested in issues related to building an IP-based core cellular network: handling terminal mobility, cell-provisioning & QoS issues, vertical handoff between two different networks as well as handling personal mobility.

There are several advantages of connecting a cellular network to the Internet. Firstly, we can easily deploy new services in the Internet and use the cellular telephone as just another IP end device. We can use the proxy mechanism to support a wide range of thin client end devices.  Secondly, we can build more interesting applications by integrating voice & data. Thirdly, we can build a cheaper telecommunication infrastructure by replacing the core circuit-switched network with the IP packet-switched network.

As part of testbed development for our studies, we have successfully built a gateway that interfaces a GSM cellular base station to the Internet. We have demonstrated the ability to make phone calls from the GSM cellular phones to computers on the Internet. The components in our design are shown in Figure 1. The "UPSim" is a PC connected to the Internet handles the GSM signaling with the cell-phone through the Base-Station. The data-path between the cell-phone and an Internet host is through another IP host (a PC), called "IPPAD" which does the inter-conversion between frames on the air and IP packets.

With our testbed, we have also demonstrated a pull application where we can use a cellular phone to read news headlines from the New York Time web page. We have also demonstrated a push application where we can use the cell phone to send voice commands to control lights, camera and other devices in an "intelligent" conference room.

Our future plan is to expand our testbed by including the Public Switched Telephone Network and a pager network so that we can address interesting research issues like mobility management, quality of service, and name mapping. We also plan to do parallel development on this testbed to include new services such as a "universal inbox" that handles personal mobility as well as other communication services.