Fibre Channel
From Computer History Wiki
Fibre Channel is an architecture, and a set of standards, and products which implement them, for creating a storage area network (SAN) which connects servers to mass storage elements. Originally using fiber optic connections, it has since been adapted to use conductor-based connection links as well.
It was designed from the start to use serial physical connections, to overcome the inherent limitations of parallel interfaces (such as SCSI); those interfaces face the issue of maintaining and determining timing coherence across all the signal lines.