The major payment card networks, including Visa, MasterCard, American Express, and Discover, founded the PCI Security Standards Council to develop a security standard to protect credit or debit card information in order to prevent, identify and respond to security breaches involving sensitive payment card data. This comprehensive standard is intended to help organizations proactively protect customer account data, and is backed by an enforcement mechanism in the form of yearly audits of merchant and processor information systems to ensure compliance.

• Build and Maintain a Secure Network
  
  • Requirement 1: Install and maintain a firewall configuration to protect cardholder data
  • Requirement 2: Do not use vendor-supplied defaults for system passwords and other security parameters
    
    
• Protect Cardholder Data
  
  • Requirement 3: Protect stored cardholder data
  • Requirement 4: Encrypt transmission of cardholder data across open, public networks