1. Cable failure

Fiber optical cable interruption leads to equipment without light, or cable damage causes excessive light attenuation. This kind of failure has a large impact, which can easily lead to no access to a large number of users.

When such a failure occurs, the number and distribution of the number of users first determine probable areas and distribution of the number of users. Arrange on the scene to test the optical signal strength with the optical power meter.

1). No light: basically judge that the cable is interrupted. The personnel on the scene can found breakpoint along the cable path. If it is the main cable failure, promptly notify the city sub-traffic maintenance to arrange line repair.

2). Too large light attenuation: focus on the inspection that whether optical cable or pigtail is damaged or loose joints. The fixed network maintenance personnel use the optical power meter to test the optical power hop by hop, find the fault point and repair.

2. Equipment power supply failure

It is a common FTTB network fault. Due to the more complex and diverse situation, failure due to power supply problems often occurs to PON equipment.

This type of failure will affect the whole unit or users’ online access to the entire building. When the status of the PON device inquired is DyingGasp (ONU outage), it can be regarded basically as outage fault. Maintenance personnel repair on the site by checking the equipment without electricity.

3. Device hardware failure

It is a common FTTB / FTTH network fault. When the status of the PON device inquired is offline, it indicates that the PON device is unknowingly offline. Maintenance personnel check on the scene. If light and electricity are under normal circumstances, it can be judged this reason. Replace the equipment and return the failure of equipment in time to the city for maintenance. In the case of thunderstorms, such failures are common.

4. ONU data failure

It is a probable FTTB network fault. If the ONU configuration data is lost or the configuration is incorrect, just check that the status of the PON device. When it is working, it indicates that the PON device works normally. Then continue to check the ONU on-line terminal and check whether the ONU has learned the MAC address of the user terminal device. Make contact with data management personnel of city operation and maintenance to find and clear fault.

5. User side failure

Check that the status of the PON device. When it is working, it indicates that the PON device is working properly. FTTB network through the "Pon network platform" inquires whether there are other normal landing users under the device; FTTH network checks whether the optical cat learns the Mac address. If there are other registered users or no Mac address learned, it can be basically judged as a single user failure. Arrange staff to find the reasons for the door, check whether the user network cable connector is loose or damaged, and check the user home router and computer settings. Help users to restore the network.