IF this function of a port is enabled, then the most significant 6 bits of the TOS (these 6 bits are also known as the DiffServ Code Point "DSCP" field, value from 0 to 63) are used to assign a priority to the packet received from this port. Please check the corresponding mapping checkbox to assign a high priority or uncheck that to assign a low priority.
4.12 IGMP
IGMP is used in multicast communication network applications where one or more servers, for example, video servers, generate multicast traffic. If you want your switch to support multimedia and IP multicast, enable this option (default is enabled). When this option is enabled, this switch only directs the multicast data packets to the ports where needed, saving bandwidth. If "Forward with high priority" option is enabled, then the IP multicast traffic will have a higher priority than other traffic.
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