SMTP & Infrastructure Providers

The "engine manufacturers." This section covers the "deeper" level of providers, like Amazon SES or PowerMTA, that provide the raw engine (the MTA or SMTP relay) that ESPs often build their platforms on top of.

15 questions in this topic

What is an SMTP provider? How does SMTP differ from an ESP? What is a relay service? What are major infrastructure senders (e.g., Amazon SES, Elastic Email)? What is a Mail Transfer Agent (MTA)? What is an MTA vendor (GreenArrow, PowerMTA, Halon, etc.)? What’s the difference between on-premise and cloud MTAs? How do SMTP services handle throttling and retries? What is a queue manager? What is connection concurrency? How do MTAs manage bounce handling? What’s the role of authentication in MTA configuration? What is DKIM signing at MTA level? What is outbound filtering and why is it used? What is inbound filtering and how is it configured?

Questions about SMTP & Infrastructure Providers