In each line of the ACL you specify one network location which you want to be able to access your easyDNS account. These can be identified by either hostname or IP address, and you can specify ranges or individual locations as suits your purposes.

If one enters an exact hostname in the field, such as laptop.example.com, when a login is attempted the IP the user is connecting from is compared to the IP that laptop.example.com resolves to. If these IPs match, the login attempt is allowed and with the correct username and password the user can log into the account. One can also use wildcards in this setup, like *.example.com, so that any connection from within the example.com domain name will be allowed.

IP addresses, and ranges of IPs, are usually entered using CIDR notation such as 192.168.12.0/24, 192.168.0.0/16, or 192.168.49.117/32. The number after the "/" indicates the size of the block based on the preceeding IP, the /32 indicating the exact IP, so with the example 192.168.49.117/32 only 192.168.49.117 would be accepted, while with 192.168.12.0/24 would allow any IPs beginning with 192.168.12. Other sizes of netblocks can be entered, if you do not know how to indicate the block for your location you will want to contact your connectivity provider or tech department to get the proper CIDR notation.

IPs can also be entered as an "IP mask" rather than in CIDR notation, such as 192.168.14.*. This notation is converted into CIDR by our system, and handled the same way as above.

Technical Note: Those who are familar with regular expressions, either Posix Regex or Perl Regex can specify hostnames or IPs in that format for greater flexibility.