For R & D testing and 200Gbps and above optical module testing, Keysight DCA-X series sampling oscilloscope and its supporting modules are used to provide comprehensive, accurate and efficient test solutions. The solution includes Keysight AWG and M8000 series error meter, which supports the test from 250Mb/s to 224Gb/s PAM4, covering multiple test items such as optical and electrical, to ensure the test reliability and stability of various optical modules in various performance indicators.