You are using the EUI-64 method of allocating the host portion of the IPv6 addresses. The MAC address of the host is f423:5634:5623. Which is the correct IP address that will be calculated for a network ID of fd00:1:1::?

When converting a MAC address to an EUI-64 host address, the first step is to split the MAC address into 6-byte sections of f42356 and 345623 and place fffe in between them, f423:56ff:fe34:5623. This gives you a 64-bit value composed of a 48-bit MAC address and a 16-bit filler. You must then invert (flip) the 7th bit. Example: f4 = 1111 0100 = flipped = 1111 0110 = f6.