This Recommendation specifies the functional architecture of deep packet inspection for future networks (e.g., software defined networking, network function virtualization etc.). This Recommendation specifies general DPI functional architecture aspects related to future networks, DPI functional architecture for software defined networking, DPI functional architecture for network function virtualization, DPI functional architecture for service function chaining and DPI as a service, DPI functional architecture for network virtualization, and DPI functional architecture for evolving mobile network.