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µC/TCP-IP supports IPv4 multicasting with IGMP. In order to receive packets addressed to a given IP IPv4 multicast group address, the stack must have been configured to support multicasting in net_cfg.h, Multicast Configuration, and that host group has to be joined.
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µC/TCP-IP supports IPv6 multicasting with MLDP. In order to receive packets addressed to a given IP IPv6 multicast group address, With IPv6 MLDP is always enabled but you might need to increase the number of group, see Multicast Configuration.
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