A. When the client side accesses 10GE LAN services, "Port Service Mapping Path" needs to be set to "MAC Transparent Mapping (10.7G)" to support the test frame function

B. When the tributary board is configured to be electrically crossed to the wavelength division side of the optical wavelength conversion board that supports the test frame, the GFP management frame is processed by the optical wavelength conversion board. Therefore, in this case, the tributary board cannot send and receive test frames

C. For GE/FE/10GE LAN services, the GFP management frame is used to send test frame messages. The test frame has two counters, which are used to count the sent and received test frames.

D. For 40GE/100GE services, test frame messages are sent directly at the MAC layer. There are three counters for test frames, which are used to count sending test frames, answering test frames, and receiving test frames.

E. For the optical wavelength conversion board with the transceiver integrated, the test frame has nothing to do with whether the board is configured with electrical crossover.