The Internet development has brought both new opportunities and risks for either retailers or consumers. For example, electronic commerce is much faster and less expensive, but this openness makes it difficult to secure. People are aware of the fact that online businesses collecting, process and distribute enormous amounts of personal data and therefore, are concerned about their unauthorized use or their use in other purposes than intended by third parties in order to gain unauthorized access to them. There are more examples of cyber criminal activities, such as: hacking, software piracy, passwords attack, service prohibition attacks, scamming, etc. Such fears led to the editing of protection policies meant to secure personal data and to develop some mechanisms to ensure the reliability and confidentiality of electronic information. Security measures include access control devices, installation of firewalls and intrusion detection devices, of some security procedures to identify and authenticate authorized users of network systems. Such mechanisms constitute the core of this study. We will also analyze security and confidentiality policy of personal data of Google Inc.