In IPv4, the localhost address is 127.0.0.1, and it is widely used for testing and development on the local machine itself.
In IPv6, the equivalent of this address is ::1
.
This address is also called loopback in IPv6 and is used for similar purposes, such as testing the network configuration on the local machine without sending traffic over the external network.
the notation ::1
is a shorthand way of writing the full address, which would be 0000:0000:0000:0000:0000:0000:0000:0001
.
In IPv6, leading zeros in each segment and long sequences of consecutive zeros can be compressed to simplify writing and reading addresses, so ::1
represents all zeros followed by a '1' at the end, indicating the loopback direction.