title: Netflix doesn't logout other open sessions with password change
body: <p>I've recently been doing a bit of web development so I've been thinking more about authentication and stuff. On Netflix I noticed there is an extra option on the Account page to de-authorize other devices. My girlfriend changed her password but I was still able to use it without re-entering the password till she logged out other devices. </p>
  
  <p>So my question is how does authentication for Netflix work if it doesn't have to locally store  your password?</p>