Multicast IPv4 address space
The IPv4 multicast address space is defined as all addresses between 224.0.0.0 and 239.255.255.255. In the classful network addressing scheme, this range is also known as the class D IPv4 address range.
It can also be defined as 224.0.0.0/4 since the leading four bits are always the same: 1110.
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