Consumer Messaging Platform — WhatsApp-Class System · View 07 of 23

Delivery and Receipt State Matrix

Every message state, what triggers it, who emits it, what the sender sees, and how long the server keeps anything at all.

Editable source SVG draw.io All views

Why a matrix

A flow diagram hides which states the server can and cannot assert
Reading down the retention column shows how little is retained per state
Reading across a row is a complete specification for one tick change

Privacy behaviour

Read receipts are reciprocal: disabling yours removes your view of others'
Group chats always report read receipts to the sender, by product decision
View-once media is destroyed server side at first play, not at expiry

Failure case

Thirty days without a device acknowledgement drops the ciphertext silently
The sender is not told; the tick simply never advances
This is the only path where a message is lost by design