title: Storing & Authenticating Users: LDAP Server vs MySQL DB?
body: <p>I was curious to know how popular online companies like Amazon and Ebay store customer credentials &amp; how they authenticate the users? I read about storing the user credentials in mySql vs LDAP server. And I was reading about using spring LDAP Authentication Provider. The book talks about really how secure it is to send encrypted passwords to LDAP server and having it authenticated there (Supposedly since the authentication happens only inside the server).</p>
  
  <p>Now I was curious to know how the big companies like Amazon &amp; Ebay does it? Whats the popular trend for online businesses when it comes to storing user credentials and their authentication mechanisms.</p>
  
  <p>I am pretty new to this, I apologize for obvious omissions.</p>