From Halopedia, the Halo wiki
Pori is a region on New Carthage. The industrial township of Kotka is located here. Kotka is home to a Hannibal Weapon Systems facility which developed the MJOLNIR Powered Assault Armor/Vanguard and MJOLNIR Powered Assault Armor/Aviator variants.
Pori is likely named after city of Pori, Finland.