What is email security gateways?

Email security gateways (ESGs) are solutions designed to protect organizations from email-borne threats, such as spam, phishing, malware, and business email compromise (BEC). They sit between the organization's email server and the internet, inspecting inbound and outbound email traffic. They commonly use techniques like anti-spam filters, anti-virus scanning, content analysis, and sender authentication protocols to identify and block malicious emails.