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In auto mode, the system utilizes the voice packets or the protocol packets such as PICA8 supported LLDP, LLDP-MED and CDP sent by the IP phone to determine whether to add the port to voice VLAN. If the source MAC address of the packets matches the OUI address, the system will automatically add the ingress port of the voice packet into the voice VLAN, and implement the QoS priority to the voice VLAN. If the source MAC address of the packets matches no OUI address, the system will learn the source MAC address of the LLDP, LLDP-MED or CDP packet as the learned OUI and add the port to the voice VLAN.
If the IP phone supports one of the protocols of LLDP, LLDP-MED or CDP, please refer to section Voice VLAN with LLDP and Voice VLAN with LLDP Compliance CDP for details about the process of protocol packets.
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