druid/docs/ingestion/streaming.md

---
id: streaming
title: "Streaming ingestion"
---

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Apache Druid can consume data streams from the following external streaming sources:

* Apache Kafka through the bundled [Kafka indexing service](kafka-ingestion.md) extension.
* Amazon Kinesis through the bundled [Kinesis indexing service](kinesis-ingestion.md) extension.

Each indexing service provides real-time data ingestion with exactly-once stream processing guarantee.
To use either of the streaming ingestion methods, you must first load the associated extension on both the Overlord and the Middle Manager. See [Loading extensions](../configuration/extensions.md#loading-extensions) for more information.

Streaming ingestion is controlled by a continuously running [supervisor](supervisor.md).
The supervisor oversees the state of indexing tasks to coordinate handoffs, manage failures, and ensure that scalability and replication requirements are maintained.
You start a supervisor by submitting a JSON specification, often referred to as the supervisor spec, either though the Druid web console or using the [Supervisor API](../api-reference/supervisor-api.md).