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

# Authentication

> How to authenticate with the Lynx SSP Ad Serving API

## Overview

All API requests to the Lynx SSP Ad Serving API require authentication using a unique API key. This ensures secure access to your account and prevents unauthorized usage.

## API Key

Your API key is provided through the `Lynx-Key` header in all API requests.

### Obtaining Your API Key

You can obtain your API key in two ways:

1. **From Display Details Page:**
   * Go to the **"Screens"** section on the Display Details page
   * Click the **"Connect Player"** button and select **"API Integration"**
   * Copy the **API Secret Key** for your production environment

2. **From User Settings:**
   * Navigate to the User Settings page
   * This page also provides the API base URLs required for integration

### Using Your API Key

Include your API key in the request header:

```bash theme={null}
Lynx-Key: your-api-key-here
```

## Security Best Practices

<Warning>
  Your api\_key is private and should never be shared with third parties. Treat it like a password to prevent unauthorized access to your account.
</Warning>

* **Keep it secure:** Never expose your API key in client-side code, public repositories, or logs
* **Environment-specific keys:** Use different keys for development and production environments

## Example Usage

```bash theme={null}
curl -X POST "https://ad.lynxssp.com/api/v1/ad/request?format=json" \
  -H "Lynx-Key: your-api-key-here" \
  -H "Content-Type: application/json" \
  -d '{
    "venue_id": "venue_123",
    "screen_id": "screen_456",
    "play_time": 1698451200
  }'
```

## Troubleshooting

### Common Authentication Errors

**401 Unauthorized**

* Check that your `Lynx-Key` header is included
* Verify that your API key is correct and active
* Ensure there are no extra spaces or characters in the key

**403 Forbidden**

* Your API key may not have permission for the requested operation
* Contact support if you believe this is an error

**Missing Header**

* Ensure the `Lynx-Key` header is properly formatted
* Header name is case-sensitive