The Extreme Networks 10421 Compatible QSFP28 to 4x25G SFP28 Direct Attach Cable operates over passive copper, which requires no additional power to ensure quality connectivity. This breakout cable is compliant with IEEE 802.3bj, SFF-8402, and SFF-8665 standards. It provides a connection of a 100G QSFP28 port on one end and to four 25G SFP28 ports on the other end and is suitable for cost-effective close-range interconnections within the equipment room of telecom operators or data centers, etc.