QSFP+ (Quad Small Form-Factor Pluggable Plus) is the workhorse optical form factor for 40 GbE compact, hot-pluggable, and built around 4×10 Gb/s electrical lanes per direction. In data centers, it enables short-reach MMF fabrics, long-reach SMF leaf–spine, and simple 4×10G breakouts. This guide demystifies QSFP+ typ...