# Content filtering and NTP

> Blocking site categories through Cloudflare DNS, and the GPS-backed NTP server on every dish.

Source: https://joinnasnet.com/en/guides/starlink/network-services/
Last updated: 2026-08-18

---

## Content filtering

Content filtering blocks categories of websites across the whole Starlink
network. Find it in the app under **Settings → Router**.

| Option | Effect |
| ------ | ------ |
| No filtering | Everything is reachable |
| Malware | Blocks sites that may host malware |
| Malware and adult content | Blocks both categories |

### How it works

It sets a custom DNS server, specifically Cloudflare for Families. When
filtering is on, the router resolves names through one of those servers, and
Cloudflare declines to resolve the blocked categories.

That mechanism explains its limits:

- **Best effort only.** DNS filtering is not enforcement, and some sites get
  through.
- **Over-blocking happens.** Legitimate sites are sometimes caught.
- **No per-site control.** The category lists belong to Cloudflare, so Starlink
  cannot add or remove individual sites, and neither can you.

If you need real control, run your own DNS or filtering on a third-party
router. See [Third-party devices](/en/guides/starlink/third-party-devices/).

## NTP

Every Starlink runs an NTP server backed by GPS time. Point your NTP client at:

```
192.168.100.1
```

The time comes from GPS, but the service is best-effort and its accuracy is not
guaranteed, so do not build anything that needs certified time on it.

## Related

- [Networking](/en/guides/starlink/router-config/networking/)
- [Third-party devices](/en/guides/starlink/third-party-devices/)