In GatorLeads you have the option to lock down Email Addresses and IP's.
This means that only certain users with a specified email address can access the Leads Instance.
For IP's, you can control access to the instance via specified IP's.
This is particularly useful if you have a lot of users based in different locations who can only have access if approved.
Select Admin -> Security -> Email Lockdown.
You will see you can enter the email domain and provide a description of why this is allowed access or who it is for.
In IP Lockdown, anyIP's which are determined to have access can have their access rights changed here.
Simply select an option from the dropdown.