There are many reasons for the instability of the network, and further tests are needed to find out the fault point in order to eliminate the fault in a targeted manner. The specific steps are as follows:

1. First, connect the telecom optical cat and other devices to ping the address of the telecom gateway or DNS server to get a value;

2. Reconnect the router (unplug other network cables) and ping；;

3. Then connect other computers and ping them when they are in normal use;

Get three values, which is bigger or there is packet loss, indicating where the problem lies. The first time, the telecommunications company's line was bad, the second time, there was something wrong with the router, and the third time, if it was abnormal, there was something wrong with the LAN.