400G QSFP DD and 200G QSFP56 high speed optical transceivers are good for big dat, cloud computing and data centers. 400G QSFP DD compliant with IEEE 802.3cm, QSFP DD CIMS 4.0.  8 channel full duplex, each channel transmitting up to 53.125Gb/s. 200G QSFP56 is four channel 4x50Gb/s which compliant with QSFP56 MSA at PAM4 encoding. Maximum link length of 100m on OM4 MMF