After installing the module you will be able to add it to a page. 

As an Administrator of the site you will be able to create IP Range records and assign these ranges to a User Account.  When the IP Address is meet or is within the Range the visitor is logged in to the system.

Tip: Create a user account and assign a role to that account.  IP address access is given to User Accounts not Roles.  You will find it easier to manage accessability by Role than by User Account.

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