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Internet Group Management Protocol (IGMP) Configuration
NET_IGMP_CFG_MAX_NBR_HOST_GRP configures the maximum number of IGMP host groups that may be joined at any one time. Each group entry requires approximately 12 bytes of RAM, plus three pointers, plus a protocol address (4 bytes assuming IPv4 address).
The number of IGMP host groups required by the application depends on how many host groups are expected to be joined at a given time. Since each configured multicast address requires its own IGMP host group, it is recommended to configure at least one host group per multicast address used by the application, plus one additional host group. Thus for a single multicast address, it is recommended to setNET_IGMP_CFG_MAX_NBR_HOST_GRP with an initial value of 2.
Socket Layer Configuration
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