Question

When creating an inbound rule in the Windows firewall, the documentation included with Windows about the remote IP addresses in under the Scope tab says:

Any IP address

Select this option to specify that the rule matches network packets that are addressed from (for inbound rules) or addressed to (for outbound rules) any IP address included in the list.

What list is it referring to? Thanks!

Answer 1

The list refers to the list for the local IP addresses (the box above).

Basically, the rule is applied to any remote IP for that rule to the machine, as long as its target IP address is in the local IP address list (unless the option for “Local IP address” is “Any IP address” as well).

Here’s an inbound example:

• In Local IP address, you only have 123.123.123.123 in the list
• In Remote IP, you select “Any IP address”
• If a request comes in from any remote IP address, but to one not in the local IP list (like 213.213.213.213), the rule is not applied
• If a request comes in from any remote IP address with a target of 123.123.123.123, the rule is applied

Here’s an outbound example:

• In Local IP address, you only have 123.123.123.123 in the list
• In Remote IP, you select “Any IP address”
• If a request is going out to any remote IP address, but the source is not in the local IP list (like 213.213.213.213), the rule is not applied
• If a request goes out to any remote IP address from a source of 123.123.123.123, the rule is applied

If, in another scenario, you have “Any IP address” selected for Local IP address and “Any IP address” selected for Remote, the rule will be applied to all requests that match that rule.