ODIN was a department, division, or position within Starfleet's Fleet Operations Center on Earth. (ENT: "Demons" set artwork)
In January of 2155, Starfleet officers G. Tachell, E. Kelly, and J. Rarick worked in (or as) ODIN.
ODIN was seen on directory listings seen on the set of "Demons".
, like many of the other divisions, departments, or positions on the listing, is a reference to NASA
terminology, in this case, the "Onboard Data Interfaces and Networks".