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You can configure combinations of these options, in which case all sets of conditions must be satisfied before access is granted; the IP range is checked first, then the referrer domain, then the password and finally the registered email address.
IP Range
To permit access only to browsers from specific IP addresses or ranges, check the option Permit access by IP range. Then, you can enter either a single IPv4 address in the format 123.234.123.234, or an IPv4 range in the format 123.234.123.234/24. This second format is known as CIDR notation and is a short form of including a whole subnet of addresses. More information on the CIDR notation is available here: Classless Inter-Domain Routing.
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