QDD-400-AOC15M=

The QDD-400-AOC15M is a 400 Gigabit active optical cable, 15 m long, with a QSFP-DD connector on each end and multimode fibre between them. Plan the route before ordering, because a fixed-length cable cannot be shortened or extended later. The rate is fixed by the cable type, so the port at each end must be set for the matching speed. The optics are sealed in the connector bodies, so there is no MPO connector to clean and no transceivers to pair. It is aimed at row-to-row and hall-scale links, such as leaf-to-spine runs, where in-rack slack is not the concern. Because it is built to a set length, stock planning is by length, so a rack plan listing each link helps ordering. The fibre jacket is far lighter and more flexible than 400G copper, which matters in dense spine-leaf rows. Both ends are permanently attached, so nothing needs cleaning, and the whole cable is replaced if either end is damaged. Cisco's 400G QSFP-DD data sheet lists it in the QDD-400-AOC family, from 1 m to 30 m, with forward error correction handled by the host platform.