System Design · Senior · Question 10 of 75
Which components are usually needed in a messenger architecture?
- ✓Correct answer: WS gateways, message storage, presence and push
- 2One server with a database that all clients poll once a second
- 3Only a CDN, since messages are static files
Explanation
Gateways hold connections and scale horizontally; pub/sub (Redis, Kafka) sits between them so a message reaches the right node. Message storage, delivery and read receipts, presence with heartbeats, push notifications, cross-device sync.