EUI64tekniikalla

EUI64tekniikalla, or EUI-64 technology, is a method used for the automatic generation of the interface identifier part of an IPv6 address. The interface identifier is the lower 64 bits of an IPv6 address, and it uniquely identifies a network interface on a given link. EUI-64 utilizes the 48-bit Media Access Control (MAC) address of a network interface card (NIC) to create this 64-bit identifier.

The process of generating an EUI-64 interface identifier involves taking the 48-bit MAC address, splitting it into two 24-bit halves. Then, the hexadecimal value FFFE is inserted in the middle. Finally, the seventh bit of the first byte of the MAC address is inverted. This inversion is done to ensure that the resulting interface identifier adheres to the Modified EUI-64 format, which is a requirement for globally unique identifiers.

EUI-64 offers several advantages, primarily simplifying network administration by eliminating the need for manual configuration of interface identifiers. It promotes automatic address assignment, which is a cornerstone of IPv6's scalability and ease of deployment. However, concerns have been raised regarding privacy, as the MAC address is embedded in the IPv6 address, potentially allowing for tracking of devices across different networks. To mitigate this, privacy extensions for IPv6 exist, which generate temporary interface identifiers that change over time.