Difference between and ::/0 in access control lists

Solution 1: 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: is IPv4 and ::/0 is the default route address for IPv6 covering all addresses.