200G QSFP56 DAC (Quad Small Form-Factor Pluggable 56 Direct Attach Copper) is a type of fiber optic transceiver that is used to connect network devices to fiber optic cables using Direct Attach Copper (DAC) cables. DAC cables are a type of copper cable that is used to connect network devices to fiber optic cables in short-distance applications, typically over distances of up to 7 meters.

200G QSFP56 DAC transceivers are designed to support data transfer rates of up to 200 gigabits per second (200G). They are typically used in high-bandwidth applications such as data centers, where a large amount of data needs to be transmitted over short distances. QSFP56 DAC transceivers are available in a variety of different form factors, including pluggable modules and rack-mountable units, and can be used with a variety of different DAC cables.

200G QSFP56 DAC transceivers are an attractive choice for network administrators who need to be able to easily connect and disconnect devices, or change the type of DAC cable being used, without having to replace the entire device. They are also useful in applications where space is limited, as they are small and compact, and can be easily installed in a variety of different networking environments.