The system includes over 66 low -earth-orbit (LEO) satellites, in order to work at low power with small (antennae and devices). This means, though, that satellites orbit the earth in less than 90 minutes, so during a typical telephone conversation, messages must be dynamically rerouted from one satellite to another. The developers describe the Iridium switching problem as equivalent to re-configuring an ATM switch every 4 minutes. Objectivity/DB is used in the base stations, for satellite routing and rerouting, and message routing and rerouting, as well as network management.
They have three facilities, each with ~50 Sparc20 servers and workstations. These facilities, in Phoenix, Washington DC, and Rome, are linked internally and among each other and 20 gateways as one distributed system. The distributed ODBMS single logical view was critical for this. They expect to generate 10 Gigabytes of data/day and will need to keep ~5 days of data online, requiring scalability. Other database problems include network management (node management, fault management), satellite control (commanding, telemetry, orbit management), and mission planning (resource scheduling).
They experienced first hand the difficulties of attempting to use an RDB with a complex data model. The bottom line was that they found it impossible to keep an RDB schema mapped to an OO design. The schema was always 2 weeks behind. Eventually they abandoned the approach and went to file based persistence in order to make the first release. A decision to use Objectivity/DB in the second release was later made, in order to regain the DBMS facilities of recovery, concurrency, scalability, and distribution.