How many categories does MA5600T/MA5680T acceptance testing manual divide acceptance testing project? (Multiple Choice)

(multiple) In the GPON network, which of the following reasons may cause the ONU to fail to go online?

MA5600T/MA5680T GPON access services in a simplified manner for the template mode excessive number of templates and configure complex issues such as optimization, thus reducing the workload of configuring and maintenance cost. Currently, only a simplified manner GPON FTTH scenario, the new GPON FTTH scene and the scene less demanding QoS can be used to simplify the service configuration mode.

(single) The value of the PROTOCOL field of the PPP protocol is 8021. What is the protocol represented?

When needed in the local MA5600T/MA5603T equipment maintenance management, can through the local login system, which interface does serial port RS - 232 serial port RJ - 45 so connector connected to?