hCaptcha - Do you use a captcha to keep out bots? hCaptcha is a drop-in replacement for reCAPTCHA that earns website owners money and helps companies get their data labeled.
Cloudflare WAF - Whether you want automatic WAF protection from known vulnerabilities or have custom WAF rules, our real-time platform can do it.
MTcaptcha - Enterprise Captcha solutions
ModSecurity - ModSecurity is an Open Source web application firewall developed by Trustwave's SpiderLabs.
GeeTest CAPTCHA - GeeTest protects your websites, mobile Apps and APIs from bot threats.
AWS WAF - AWS WAF is a web application firewall that helps protect your web applications from common web exploits.