The scenario describes distributed scraping where each individual IP stays below request-rate thresholds. A simple DoS threshold is weak here because the attacker avoids volume-based detection per source. Static blocklists are also ineffective because many botnet IPs may appear only once or rotate frequently. Blocking every non-allowlisted user agent would cause severe false positives and is easy for bots to evade by spoofing headers. FortiWeb bot mitigation is the correct control because it can evaluate behavior beyond source IP volume. Device fingerprinting, browser behavior, headers, JavaScript challenges, and client characteristics help correlate suspicious automation even when requests are spread across many addresses. Therefore, bot mitigation with behavioral/device fingerprinting is the strongest answer.

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