Difference between 0.0.0.0/0 and ::/0 in access control lists
When setting up access control lists, what's the difference between 0.0.0.0/0
and ::/0
?
I'm seeing this for an AWS EC2 instance I'm setting up
Solution 1:
0.0.0.0/0 is the IPv4 everything - all possible IPv4 addresses.
::/0 is the IPv6 equivalent of that.
You can, for example, allow IPv4 and disallow IPv6 or vice versa.
@kasperd mentions:
It should be noted that depending on implementation ::/0 can mean either all IPv6 addresses or all IPv4 and IPv6 addresses. That's because IPv4 addresses can be mapped into IPv6 addresses ::ffff:0:0/96
More info on IPv6 is here.
Solution 2:
0.0.0.0/0
is IPv4 and ::/0
is the default route address for IPv6 covering all addresses.