There are four 100 Gigabit QSFP28 ports. Use them to connect other 100 Gigabit devices or grab a breakout cable to connect multiple 25 Gigabit devices: each port is connected to four 25 Gigabit lines, allowing you to connect 16 x 25 Gigabit devices. In fact, you can mix and match all kinds of connections this way: 100 Gigabits on one port, 40 Gigabits on the other, 4x25 Gigabits on the third, and maybe even some 10G or 1G cables on the fourth. The mighty Marvell DX4310 switch-chip will handle everything without breaking a sweat!