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New Member

how does an ipv6 link local address is been generated...i have lots of doubts with this aspects ...

i can not see any mac address in link local address

Cisco Employee

Hi Kumar,You wont see the MAC

Hi Kumar,

You wont see the MAC address as such appended to FE80::. It is a 2 step process.

1. The 48 bits MAC address will be converted to 64 bits identifier by including FFFE in the middle. FOr example, MAC AAAA.BBBB.CCCC will be converted to AAAA:BBFF:FEBB:CCCC (16*4=64 bits).

2. Now the 7th bit of the MAC address will be flipped. In this case, AAAA on converting the first octect to binary will be 10101010. Now flipping the 7th bit will make it as 10101000 which is A8AA in hex.

So your link local address will be FE80::A8AA:BBFF:FEBB:CCCC.

You can try to apply the same in your setup and see if yo get the link-local from your MAC.