What is the meaning of single port manager?

(DoD) Through its transportation component commands, the US Transportation Command is the Department of Defense-designated single port manager for all common-user aerial and seaports worldwide. The single port manager performs those functions necessary to support the strategic flow of the deploying forces' equipment and sustainment from the aerial and seaport of embarkation and hand-off to the combatant commander in the aerial and seaport of debarkation. The single port manager is responsible for providing strategic deployment status information to the combatant commander and to manage workload of the aerial port of debarkation and seaport of debarkation operator based on the commander's priorities and guidance. The single port manager is responsible through all phases of the theater aerial and seaport operations continuum, from a unimproved airfield and bare beach deployment to a commercial contract supported deployment. Also called SPM. See also Surface Deployment and Distribution Command; transportation component command; United States Transportation Command.