IP address
IPv4
Special IPs:
-
0.0.0.0
Non-routable meta address.
Used to designate Invalid, unknown targets.
Also used as host to listen up to all public IPs. (
flask run -h 0.0.0.0
)
-
127.0.0.1
one of loopback address (starting from
127
) used to establish connection with the same machine.
-
localhost
Usually point to
127.0.0.1
Defined in
/etc/hosts
:127.0.0.1 localhost ::1 localhost // ipv6
IPv6
128bit
NAT (Network Address Translation)
用于缓解IPv4不足,指的是路由器自动修改IP报文实现LAN/WAN之间转换的过程。