Hello,
WAN CONFIGURATION - BRIDGE
1. In the navigation tree on the left, choose the WAN > WAN Configuration. In the pane on the right, click New. In the dialog box that is displayed, set Mode to Bridge WAN, as shown in Figure 1.
Figure 1. WAN Configuration - bridge

2. Click Apply.
Table 1 describes the parameters related to the WAN in bridge mode.
Table 1. Parameters related to the WAN in bridge mode
Parameter | Description |
|---|
Enable WAN | Indicates whether to enable the WAN connection. |
Encapsulation Mode | Indicates the encapsulation mode of a WAN interface. It can be set to IPoE or PPPoE. |
Protocol Type | Indicates the protocol type of a WAN interface. It can be set to IPv4, IPv6, or IPv4/IPv6 dual-stack. |
WAN Mode | Indicates the WAN interface mode. It can be set to Bridge WAN or Route WAN. |
Service Type | Indicates the service type of the WAN interface. It is always set to INTERNET. |
Enable VLAN | Selects this check box to set VLAN ID and 802.1p priority. |
VLAN ID | Indicates the VLAN ID. It ranges from 1 to 4094. The VLAN ID must be the same as the C-VLAN ID on the OLT. |
802.1p Policy | Indicates the 802.1p priority policy. Use specified value: indicates that a specified priority value is used. If you select this option, you need to set the 802.1p parameter. Copy from IP precedence: indicates that the priority is copied from the ToS field in the IP header of the user-side packets. If the received packet is not an IP packet or the packet does not carry the 802.1p priority, the default 802.1p priority is used. If you select this option, you need to set the Default 802.1p parameter.
|
Binding Options | Used to bind the WAN interface to the LAN port or to the wireless SSID. NOTE: Before setting the binding options, set the work mode of the LAN port to route or set the wireless SSID. The binding options can be set only after the work mode or wireless SSID is successfully set. |
Multicast VLAN ID | The multicast VLAN ID ranges from 1 to 4094. The multicast VLAN ID must be the same as the multicast VLAN ID on the OLT. |
NOTES
WAN in route mode: The ONT functions as a gateway. The IP address of the ONT can be obtained through DHCP, Static, or PPPoE. The IP address of the PC connected to the ONT can be obtained from the DHCP address pool of the ONT or can be set manually.
WAN in bridge mode: The ONT functions as a relay and does not process data. The ONT does not obtain the IP address allocated by the upper-layer device and it does not allow manual configuration of a static IP address. The IP address of the device connected to the ONT can be obtained through DHCP, PPPoE, or static.
In the case of the DHCP mode, you need to set the DHCP relay. After the configuration is complete, the user-side IP address is obtained from the upper-layer device.
In the case of the PPPoE mode, the user-side IP address is obtained through PPPoE authentication of the upper-layer device.
Detail
https://forum.huawei.com/enterprise/en/huawei-ont-bridge-mode-introduction/thread/498679-100181
Thanks