Cisco QSFP28 is a high-speed, high-density optical transceiver module designed for use in data centers and other high-speed networking applications. It supports up to 28 Gbps of data transfer rate and is compatible with the QSFP+ form factor. It is designed to provide a cost-effective solution for high-speed data transmission over long distances. It is also backward compatible with existing QSFP+ transceivers, allowing for easy integration into existing networks. The QSFP28 is an ideal choice for data centers and other high-speed networking applications that require high-speed data transmission over long distances.