deep packet inspection

深層封包檢測這技術, 各類技術的界線越來越模糊, 例如, ADC的廠商
已說它們可做firewall的工作了, Firewall也加入更多的頻寬管理功能

來個分類

• Firewall - zone security policy enforcement/id integration
• Load balancer/ADC (layer7) - content manipulation/host liveness
• bandwidth control/shaper 
• PCEF -charging/qos enforcement/telecom integration
• cache (static/video) - hierarchical storage/video site content fetch customization 
• Session border controller - SIP/IMS
• diameter DRA/DEA - telecom signaling gateway
• Application performance management( APM)
• Carrier grade NAT -ALG