epostrelay

An epostrelay is a system or service that forwards electronic mail messages between mail servers or from client applications to recipient domains. It acts as an intermediary to route, filter, and deliver messages, allowing organizations to manage outbound and inbound email traffic from a centralized point.

In typical deployments, an epostrelay runs an SMTP server that accepts outbound mail from internal applications or user mail clients, applies policy, authenticates senders, checks reputation, and relays messages to destination servers or upstream providers. It maintains message queues, implements retry logic, and records delivery events for auditing.

Organizations deploy epostrelay on premises, in virtual environments, or as a cloud service. It often integrates with existing mail transfer agents and security infrastructure. Common features include TLS encryption, SPF and DKIM verification, DMARC enforcement, rate limiting, bounce handling, and detailed logging.

Security and compliance considerations include protecting against abuse and spam, restricting access to authorized hosts, and retaining logs in accordance with local laws and privacy regulations. A well-managed epostrelay helps improve deliverability, preserve sender reputation, and reduce exposure of internal mail systems to the internet. Related concepts include mail transfer agents and email delivery platforms.