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ESP Architecture & Scaling

How to "build a bigger fleet." This section covers how large senders scale their infrastructure by adding more IPs (IP Pools), more subdomains, and dedicated MTAs for different mail streams (e.g., one for "password resets," one for "newsletters").

13 questions in this topic

Questions about ESP Architecture & Scaling

How do ESPs scale to send billions of emails? What are MTA clusters? What is sharding in message storage? How do ESPs distribute sending load? What’s the difference between horizontal and vertical scaling? How does message deduplication work? How do ESPs prevent cross-customer contamination (reputation-wise)? What is a sending node or data center? What are regional routing rules (GDPR, data residency)? What happens when an ESP data center goes down? How do ESPs manage backups and disaster recovery? What is HA (High Availability) in email delivery? What are ESP failover strategies?