Geolocation-based filtering and senderbase reputation filtering are two features of Cisco Email Security that can be added to a Sender Group to protect an organization against email threats. Geolocation-based filtering allows Cisco ESA to accept or reject connections from email servers based on their geographic location, such as country or continent. Senderbase reputation filtering allows Cisco ESA to reject or throttle connections from email servers based on their reputation score, which is calculated by Talos using sensor information from various sources.