Hi, dear user.
Universal Plug and Play (UPnP) is the name of a group of protocols. The UPnP supports zero-configuration networking and automatic discovery of different network devices. If the UPnP is enabled, the UPnP-enabled device can be dynamically connected to the network to obtain the IP address, obtain the transfer performance, discover other devices, and learn the performance of the other devices. The UPnP-enabled device can be automatically disconnected from the network, without affecting the device or other devices.
When the UPnP is enabled, the LAN-side PC automatically finds the DSL home gateway, which is considered as a peripheral device of the PC and is plug-and-play. After running application software on the PC, port mapping entries are automatically generated on the DSL home gateway through the UPnP protocol, thus improving the running speed.
To configure the UPnP function, perform the following steps:
In the navigation tree on the left, choose Advanced Configuration > Application > UPnP Function. In the pane on the right, you can determine whether to enable the UPnP, as shown in the following figure.

Click Apply.
Hopes can help you.