UDP: User Datagram Protocol
UEFM: Universal Electronic Freight Management
UN: User Need
UP: User Permissions
UPER: Unaligned Packed Encoding Rules
UPWP: Unified Planning Work Program
USB: Universal Serial Bus
USDOT: United States Department of Transportation
USR: User Service Requirement
US-VISIT: United States Visitor and Immigrant Status Indicator Technology
UTC: Universal Time, Coordinated