Link Protector includes the same core dtect security features available in the API, designed to detect and block fraudulent or low-quality activity before it reaches your survey or landing page.
You can choose from preset security configurations that automatically apply a combination of protections based on your goal, or open Customize Security Features to toggle individual checks manually.
How Billing Works in Link Protector
Link Protector creates a billable session only after a participant clicks I agree.
If the participant clicks "I do not agree," no session is created, and nothing is billed. If the participant agrees and then closes the page, the session is billed and marked Dropped. If the participant agrees and is then blocked, the session is billed. If the participant agrees and reaches your link, the session is billed.
All billable sessions appear in exports.
Each click on the entry link creates a new session. Re-entering the link generates an additional billable session.
Security Presets
Presets make it easy to set up protection in one click. Each preset combines multiple features to balance fraud prevention and participant conversion.
Security Options
If you prefer more control, select Customize Security Features to enable or disable individual checks. Each setting corresponds to the same detection layer available in the dtect API, allowing you to fine-tune your configuration.
Available Security Features
| Signal | What It Checks |
| IP Duplication |
Detects repeated entries from the same IP address after a prior session has reached a final outcome. A participant is flagged as a Duplicate IP only if a previous session from that IP resulted in an Allowed or Blocked outcome. |
| Device Duplication |
Detects repeated entries using the same device fingerprint after a prior session has reached a final outcome. A device is considered a duplicate only if a previous session from that device was Allowed or Blocked. |
| Duplicate ID |
Detects repeated use of the same ID value passed to Link Protector. An ID is considered a duplicate only if a previous session with that ID was Allowed or Blocked. |
| Location Lock | IP geolocation is outside the list of allowed countries. |
| Automation Detection | Behavior patterns that look like automated or scripted activity rather than a real person. |
| IP Blocklist | IP address appears on known threat or fraud lists. |
| Untrusted Browser/OS | Browser or operating system version is commonly associated with spoofing and automation. |
| Quality Questions | Flags if the participant failed validation through quality questions. |
| AI Detection | Flags if AI tools or behavior patterns were detected during the session. |
| VPN Usage | Traffic appears to be coming from a VPN or similar proxy service. |
| Device Tampering | Device signals (for example user agent, timezone, language) are inconsistent in a way that suggests tampering or masking of the real setup. |
| Virtual Machine | Session is running inside virtual machine software (which is used for testing or masking activity) instead of a standard desktop or mobile environment. |
| Dev Tools | Browser developer tools were opened while Link Protector was running. |
| Location Validation | Browser timezone does not match the IP-based location. |
| Privacy-Focused Settings | Key browser information (device, OS, or location signals) is hidden or randomized, often due to privacy tools, hardened browsers, or aggressive ad blockers. |
| Tor Exit Node | Traffic is routed through a Tor exit node, which can hide the real source of the connection. |
| High-Activity Device | The same device fingerprint appears across many entries or projects, suggesting heavy reuse or sharing. |
| Incognito Mode | Participant is browsing in a private or incognito window. |
How Duplicate Checks Work
Duplicate-based checks (Duplicate ID, Duplicate IP, and Duplicate Device) evaluate prior sessions only after a participant has reached a final outcome.
- Only sessions that were Allowed or Blocked establish duplicate history.
- Sessions marked Dropped (for example, when a participant abandons before checks complete) are ignored.
- If a duplicate check is disabled, prior session history for that signal is ignored, and the participant is evaluated only against the checks that are currently enabled.
Each click on an entry link still creates a new billable session once the participant clicks I agree.
Previous: Creating a Link Protector
Next: Managing Link Protectors
Comments
0 comments
Please sign in to leave a comment.