Adaptive Challenge
Not every user sees the same challenge. SilentShield adapts the difficulty based on the behavior score.
5 Challenge Levels
| Level | What Happens | User Experience |
|---|---|---|
| Pass | No challenge — user is clearly human | Invisible |
| Easy | Invisible proof of work, 18 bits (~260,000 hashes) | Invisible |
| Medium | Proof of work, 20 bits (~1 million hashes) | Invisible |
| Hard | Proof-of-Work + Math CAPTCHA as fallback | Visible if PoW fails |
| Block | Request is rejected | 403 error |
Automatic Escalation
After 3 incorrect CAPTCHA answers, the difficulty is automatically increased. This prevents brute-force solving attempts.