In the case of MikroTik, it generates the link local addresses automatically. When we enable the IPv6 packet we will see that in IPv6 -> address all the link local addresses were generated. Additionally, if we are going to enter through winbox, the local link address will appear in the Neighbors tab, which we only have to select. Remember that to enter the device via local link we must be on the same subnet.

Link-Local addresses in IPv6 are unique for each network interface within a local network segment or link, and are used for communication within the same physical network (link segment) that is not routed beyond it.

These addresses are automatically generated for each network interface that has IPv6 enabled, using the prefix FE80::/10 followed by the last 64 bits which are usually derived from the MAC address of the interface in a process known as EUI-64, although there are other methods to generate the remaining part of the address.

To discover and communicate with devices on the same local network, including routers, IPv6 uses the NDP (Neighbor Discovery Protocol) protocol, which is the equivalent of ARP in IPv4 but much more robust and with more features.

How to Know the Link-Local Address to Access a Router?

To determine the IPv6 Link-Local address of a router on your local network, you can use several strategies:

1. Router Interface: The most direct way is to look at the router's configuration through its web interface or CLI (Command Line Interface). The Link-Local address is usually clearly listed in the interface configuration.
2. NDP or Neighborhood Discovery: You can use network discovery tools or specific operating system commands to list the devices and their addresses on your link-local segment. For example, on Windows systems, you can use the command ipconfig to see all the IPv6 addresses on your machine, including Link-Local addresses. To view the addresses of other devices on your network, you can use ping with the Link-Local address or use tools like ndp -an on Unix/Linux systems to see the addresses of neighbors.
3. ICMPv6 Echo Requests: As in IPv4, you can try to ping the router's Link-Local address if you know it.
4. DNS and DHCPv6: Although Link-Local addresses are not routed and therefore not as directly useful for connecting over broader networks, internal domain name systems (DNS) or a DHCPv6 server may be configured to resolve link-local names. host to Link-Local addresses on a local network.

Key Differences with the MAC Address in IPv4

• While in IPv4 communication between devices on the same network segment uses MAC addresses through ARP to resolve IP addresses to MAC addresses, IPv6 uses NDP for neighbor discovery and address resolution, among other functions, making use of the Link-Local addresses.
• The Link-Local address in IPv6 is used for communication on the same link and does not require DHCP or manual configuration to be established, unlike IPv4 addresses, which may require DHCP to be assigned or manually configured.

In summary, although Link-Local addresses are dynamic and automatically generated, there are mechanisms built into IPv6 such as NDP to discover them and use them for local communication, offering a more automated and secure process for identifying and accessing devices within a network. local.