Which address is within the IPv6 link-local address scope?
Click on the arrows to vote for the correct answer
A. B. C. D.D
In the Internet Protocol Version 6 (IPv6), the address block fe80::/10 has been reserved for link-local unicast addressing. To conform to standard /64 addressing on subnets, the actual link local addresses are assigned with the prefix fe80::/64. The 54 bits after the most significant ten bits must be zero.
https://en.wikipedia.org/wiki/Link-local_address#IPv6The correct answer is option D, which represents an IPv6 link-local address.
Explanation:
IPv6 addresses are 128-bit long and are divided into eight 16-bit hexadecimal blocks separated by colons (:). The four most significant bits of the first block define the type of IPv6 address. Link-local addresses have an address type of 1111 1110 10, which translates to FE80 in hexadecimal notation.
In option A, the address starts with F8, which does not correspond to the link-local address type. This address belongs to the unique local address (ULA) range.
In option B, the address starts with FC, which is reserved for ULA. ULA addresses are used for private networks, similar to IPv4 private addresses.
In option C, the address does not start with the FE80 link-local prefix, but instead starts with 2001, which is a global unicast address prefix. Global unicast addresses are routable on the public internet.
Option D starts with FE80, which is the correct prefix for link-local addresses. The following zeroes in the address (::) indicate that the interface identifier is set to zeros. The interface identifier is the last 64 bits of the IPv6 address, and it is used to identify an interface on a network. In this case, the interface identifier is set to zeros, indicating that the address belongs to the node's local network.
In summary, the correct answer is D because it has the correct prefix for link-local addresses and the correct format.