Network operators require better network observability in order to use the data acquired to better support their business needs such as improving QoE, customer care, and security. The network data plane needs to be interactively programmable to support such applications in real time and on demand. This is a further stretch of the open programmable data plane. We developed the protocol oblivious forwarding technology, protocol, and prototype to show how this is achieved in an efficient way. POF allow users to dynamically install probes at any places in the data plane and run customized actions to monitor the data plane states and events. We show our system could be the foundation of a networking big data analytics platform.