An allowlist is a security measure that specifies a set of trusted entities, such as IP addresses, websites, applications, or email addresses, that are granted permission to access a particular system or network. System administrators can effectively control the data flow and limit potential security threats by implementing an allowlist. Allowlists operate under the principle of “deny by default, allow by exception“, meaning that only the entities specified in the allowlist can access the system while all others are denied by default.
- IP allowlist: A list of trusted IP addresses that are permitted to access a network or server.
- Email allowlist: A list of trusted email addresses that are allowed to send messages to a user’s inbox, bypassing spam filters.
- Website allowlist: A list of trusted websites that a user or network can access, often used in corporate environments or parental control settings.
- Regularly review and update your allowlists to ensure they include only necessary entities.
- Be wary of over-reliance on allowlists — they should be part of a multi-layered security strategy.
- Consider using network monitoring tools to keep an eye on the activities of listed entities, ensuring they maintain their trusted status.