Many network devices implement capabilities to manipulate traffic depending on the application. Examples include a firewall or a load balancer. These are based on Layer 2-4 packet-based classifications such as port or protocol, or signature recognition. Although configurable or extensible via scripting, they are not generally programmable. We present an architecture extending classification to programmable, semantic Layer 5-7 capabilities. The architecture has programmable handling of that classified traffic, which are message flows, not packets. This has led us to a new, in-network message streaming based programming model. Finally, we present a series of network platform capabilities delivered as components, from precision timing to programmable QoS to network identity.