How to realize interconnection between 100G and 10G/25G/40G through optical modules

QSFP28 package has become a 100G mainstream optical module with smaller volume, power consumption and price advantages. In practical applications, how should we solve the interconnection requirements between 100G ports and 40G, 25G, 10G ports? Here are some common solutions.

1. QSFP28 port and QSFP+port interconnect

We need to change the switch port configuration to run in 40G mode, and then use 40G QSFP+to QSFP+DAC high-speed cable, 40G QSFP+to QSFP+AOC active optical cable, or 40G QSFP+SR4 optical module with 12 core MPO optical jumper to realize the interconnection between 100G equipment and 40G equipment.

2. QSFP28 port and SFP28 port interconnect

We can use 100G QSFP28 to 4 * 25G SFP28 DAC high-speed cable, 100G QSFP28 to 4 * 25G SFP28 AOC active optical cable, or use 8/12 core MPO-4 * duplex LC branch jumper to connect 100G QSFP28 SR4 optical module with four 25G SFP28 SRs, thus realizing the interconnection between 100G devices and 25G devices.