OpenFabrics Interfaces (OFI) is a framework focused on exporting fabric communication services to applications. OFI is best described as a collection of libraries and applications used to export fabric services. The key components of OFI are: application interfaces, provider libraries, kernel services, daemons, and test applications.

Libfabric is a core component of OFI. It is the library that defines and exports the user-space API of OFI, and is typically the only software that applications deal with directly. It works in conjunction with provider libraries, which are often integrated directly into libfabric.