Detailed symptom: 1. No tone can be heard when a user takes the phone off the hook. When the phone is called, an unallocated number is prompted. The VoIP indicator of the IAD is on. 2. The user can make phone calls normally. Networking:
1. An unallocated number is prompted when the phone is called. In this case, check the data of the softswitch. No configuration data is found. Add data to the softswitch. An unallocated number is not prompted when the phone is called. The IAD, however, still cannot be registered. 2. Check the data configuration of the MA5680T. No problem is found. 3. It is suspected that the forwarding fails. Capture packets and analyze the packets. The MA5680T and HG813E forward the IAD registration request to the upper layer device, but do not receive any response. 4. Log in to the NE40. Data is configured on ports 4 and 5. Port 4, however, is in the DOWN state. No data exists on port 6 but port 5 is in the UP state. Enable ports 4 and 5 of the NE40. As a result, the problem is solved.
1. The data configuration is incorrect. 2. Devices cannot forward data normally. 3. The upper layer device is faulty.