G. Medina was a Human 22nd century officer of Starfleet.
In 2151, he was named as a Mission Ops officer on a dedication plaque of the Enterprise NX-01. (ENT: "Broken Bow", Enterprise)
In January of 2155, he was named as a Telemetry officer on directory placards at the Fleet Operations Center, Sol Sector. His office was in room #3453. (ENT: "Demons", directories)