Enforcing network service level agreements in a network infrastructure element comprises receiving, at the network infrastructure element, an application-layer message comprising one or more of the packets; forwarding the application-layer message toward a destination endpoint and concurrently copying the application-layer message without disrupting the forwarding; using the copied application-layer message, discovering one or more applications or services that are using the network; using the copied application-layer message, identifying one or more network-layer condition metrics, and identifying one or more application-layer condition metrics; determining, based on the identified network-layer condition metrics and the application-layer condition metrics, whether one or more conditions of a service level agreement are violated; and in response to determining a violation, performing one or more responsive operations on one or more network elements.