RFC 4291:IP Version 6 Addressing Architecture
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64 Bit


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... start with the binary value 000, Interface IDs are required to be 64 bits long and to be constructed in Modified EUI-64 format. ...
... | bits | 54 bits | 64 bits | +----------+-------------------------+----------------------------+ |1111111010| 0 | interface ID ...
... | bits | 54 bits | 64 bits | +----------+-------------------------+----------------------------+ |1111111011| subnet ...



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