Troubleshooting: When troubleshooting devices, administrators must often switch back and forth between working with IP addresses and hardware addresses.Address harmonization: Administrators no longer must keep track of two separate, unrelated addresses for each device.Support for autoconfiguration: It is easy to generate an appropriate globally routable local address from any hardware device using its hardware address and a process such as SLAAC.More specifically, having device hardware addresses and IPv6 addresses directly linked provides value in the following areas: The benefits of EUI-64 generally relate to practical considerations: simplicity and administrative efficiency. Once again, if you do the math, you can see that if you apply the EUI-64 process to the 2001:ABCD:1234:5678::/64 prefix along with the MAC address of the particular interface, the result is the IPv6 address shown above. The resulting IPv6 global unicast address has become: Note that the link-local address that we previously manually assigned appears in the output of the IPv6 information of this interface. Take a look at this series of commands and their results. On a Cisco IOS device, as soon as you enable the IPv6 capability on an interface, the device will automatically generate a link-local address using the EUI-64 process by default. Link-local addresses are of the form FE80::/10. Link-local addresses, as the name suggests, have only local significance, so they are never routed. Remember that the link-local IPv6 address is an IPv6 address that is automatically generated and assigned to an active IPv6 interface. The first scenario involves generating a link-local IPv6 address on the interface of a Cisco router. We’ll examine two particular cases that we often see on Cisco IOS devices. Let’s take a look at how EUI-64 actually operates on a real device. Real-world example of EUI-64 configuration It is used to differentiate individual devices or interfaces within the same network or subnet. The interface identifier created via the EUI-64 process serves as the device-unique portion of the address. This address can then be used by a device to access both local networks and the global Internet.The network prefix and interface identifier are concatenated to make the final (global unicast) IPv6 address.EUI-64 is used to map the MAC address into a 64-bit EUI-64 interface identifier.The MAC address comes from the hardware device.The leftmost 64 bits of the address come from the network prefix, which defines the network portion of the address.Now that we have seen how EUI-64 mapping works, let’s pause for a bit of a recap and see how the various pieces fit together in IPv6:
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |