The technology is called Message Queuing Telemetry Transport (MQTT), an IBM-developed protocol for real-time messaging over networks with low power and bandwidth. MQTT is now under the hood within Facebook’s iOS app’s messaging features, part of Facebook’s efforts to pull in the features from its native Messenger app.
“We use MQTT to update notifications, messages, and bookmarks. At application startup, we walk the dependency graph and ensure that our MQTT service has started before we start listening for new notifications. Even as we add new features, our modular system ensures that our application setup happens in the right place, at the right time,” wrote Facebook engineer Jonathan Dann on the company’s engineering blog last week.
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