Voice communication is essential to any manned exploration of Mars, and the National Aeronautics and Space Administration (NASA) has already completed a successful test involving IP telephony. A distributed IP PBX from Shoreline Communications, the specialist in enterprise IP voice systems(TM), provided the infrastructure linking the Utah desert test site with NASA Ames Research Center in Mountain View, Calif. and NASA Glenn Research Center in Cleveland, Ohio. The test site was one of the desert and arctic habitat facilities maintained by the Mars Society — a private international organization dedicated to the exploration of the Red Planet — to simulate harsh conditions on such remote planetary surfaces. Any voice system used by NASA in the Mars Mobile Agents pilot faced a number of challenges, including: