title: On a web shopping cart written in PHP, should I check IP address everytime?
body: <p>Are too many people on rotating IP for this to be a good security measure (among others of course) or is this a standard practice?</p>
  
  <p>Also can anybody enlighten me on some concepts I should pay particular attention to in securing a shopping cart? </p>
  
  <p>So far I have form validation, rotating session keys, no sensitive information is stored as a cookie or by javascript, SSL encryption, and all SQL is escaped.</p>