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 ## SSL
 
    * https://www.ssllabs.com/ssltest/index.html - This service performs a deep analysis of the configuration of any SSL web server on the public Internet.
-   * http://certdb.com/ - SSL/TLS data provider service. Collect the data about digital certificates - issuers, organisation, whois, expiration dates, etc... Plus, has handy filters for convenience.
+   * https://certobserver.com/ct-search - Search Certificate Transparency logs for SSL/TLS certificates issued for a domain.
    * https://raymii.org/s/tutorials/Strong_SSL_Security_On_nginx.html - Strong SSL Security on nginx
    * https://weakdh.org/ - Weak Diffie-Hellman and the Logjam Attack
    * https://letsencrypt.org/ - Let’s Encrypt is a new Certificate Authority: It’s free, automated, and open.