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In the navigation tree on the left, choose WAN > WAN Configuration, set 802.1p policy.
Indicates the 802.1p priority policy.
Use specified value: indicates that 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.

If the ONT is customized for the ISP, the 802.1p policy(QoS configuration) cannot be modified. In this case, contact the ISP for a solution.
Typically, if there is no failure, the effective solution to increase network speed is to upgrade bandwidth.
Thanks!