> For the complete documentation index, see [llms.txt](https://docs.qpoint.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.qpoint.io/getting-started/qscan.md).

# Qscan

QScan is Qpoint's PII detection service for HTTP traffic captured by Qtap. It uses machine learning models to automatically identify sensitive data -- such as names, email addresses, credit card numbers, and social security numbers -- flowing through your APIs.

### How It Works

QScan operates as an asynchronous scanning pipeline:

1. **Qtap** captures HTTP request and response payloads and stores them as artifacts in S3-compatible object storage
2. **Pulse** schedules scan jobs for new artifacts
3. **QScan** polls Pulse for pending jobs, pulls artifacts from S3, scans them using ML models, and reports results back to Pulse
4. **Pulse** surfaces PII findings in your dashboards

{% hint style="info" %}
QScan must have network access to both your S3 storage endpoint and the Pulse API. It does not need to run alongside Qtap -- it can be deployed anywhere with the required connectivity.
{% endhint %}

### Detection Models

QScan combines multiple detection engines for comprehensive coverage:

* **Piiranha** -- transformer-based NER model optimized for PII detection
* **Presidio** -- Microsoft's rule-based and ML-powered PII analyzer
* **Flair NER** -- sequence labeling model for named entity recognition

Results from all models are merged and deduplicated to minimize false negatives.

### Key Features

* **Multi-model detection**: Three complementary engines for high recall across PII types
* **GPU acceleration**: Optional NVIDIA GPU support for faster inference
* **Horizontal scaling**: Deploy multiple instances with configurable poller and scanner counts
* **Prometheus metrics**: Built-in metrics endpoint for monitoring scan throughput and health
* **S3-compatible storage**: Works with AWS S3, Google Cloud Storage, MinIO, and any S3-compatible endpoint
* **Automatic credential handling**: When using Qpoint's managed storage, the registration token is used for S3 authentication automatically