The OUSP 2000 supports up to two Sonet interfaces in any combination of OC-3, OC-12 or OC-48. The unit also supports up to six standard GBIC (gigabit interface converter) interfaces for Gigabit Ethernet or Fibre Channel connectors. Akara supplied me with two OUSP 2000s, both with an OC-12 and an OC-48 interface. On the local side, Akara installed two gigabit Fibre Channel and one Gigabit Ethernet GBIC.
The first new term I had to learn was virtual facility, which Akara uses in reference to the physical Sonet connection between the OUSP units. The virtual facility defines the point-to-point connection between two OUSP 2000s and the bandwidth available to that connection. In my case, two virtual facilities were defined--one for the OC-48 and one for the OC-12. You need to define the virtual facilities initially, or if your Sonet connection changes.