> ## Documentation Index
> Fetch the complete documentation index at: https://docs.platform.pink/llms.txt
> Use this file to discover all available pages before exploring further.

# Transmissions

> Understanding how events flow through Pink Platform via transmissions

## Overview

Transmissions are the core mechanism for tracking event flow through Pink Platform. They provide complete visibility into how events move from their source to all intended recipients, ensuring reliable delivery and full traceability.

<Note>
  All developer interactions with Pink Platform happen through events that are
  delivered via transmissions. Whether you're sending data to the platform or
  receiving notifications from it, transmissions ensure reliable event
  delivery.
</Note>

## Transmission Types

<CardGroup cols={2}>
  <Card title="Inbound Transmissions" icon="arrow-down">
    Created when an event first enters Pink Platform. Serves as the entry
    point and audit trail for the original event, containing the complete
    event payload and metadata.
  </Card>

  <Card title="Outbound Transmissions" icon="arrow-up">
    Created for each recipient that should receive the event. One inbound
    transmission generates multiple outbound transmissions based on routing
    rules.
  </Card>
</CardGroup>

## Transmission Flow

The flow between inbound and outbound transmissions follows a **one-to-many** pattern through Pink Platform:

```mermaid theme={null}
graph TD
    A[Inbound Transmission] --> B[Pink Platform]
    B --> C["Outbound Transmission 1<br/>→ i.e. for Inventory Application"]
    B --> D["Outbound Transmission 2<br/>→ i.e. for Billing Application"]

    classDef pinkPlatform fill:#ff69b4,stroke:#d1477a,stroke-width:2px,color:#fff
    class B pinkPlatform
```

<Warning>
  If an inbound transmission fails to process, no outbound transmissions will
  be created. This ensures data consistency and prevents partial event
  delivery.
</Warning>

## Benefits of Transmissions

<CardGroup cols={2}>
  <Card title="Automatic Retries" icon="arrows-rotate">
    Failed transmissions are automatically retried with exponential backoff
    strategy
  </Card>

  <Card title="Dead Letter Queue" icon="inbox-out">
    Persistently failed transmissions are moved to a dead letter queue for
    investigation
  </Card>

  <Card title="Delivery Confirmation" icon="check">
    Real-time status updates and delivery confirmations for all
    transmissions
  </Card>

  <Card title="Full Audit Trail" icon="list-check">
    Complete traceability from source event to final delivery status
  </Card>
</CardGroup>