Surveillance and reconnaissance applications such as military in wireless sensor networks require timely transfer of important data (i.e., the detection of enemy troops and vehicles) to a remote base station or sink node. Unfortunately, picking up the reliable routing path to deliver the data in realtime is difficult because of various interferences, often environmental changes, and so on. Thus, routing protocols based on the link quality to select the routing path are affected by those kinds of factors. In this paper, we propose a reliable routing mechanism that provides real-time transfer of the important data. In other words, we provide the weighted link quality metric that reflect the TX/RX traffic flow to select the reliable route over the routing path. Moreover, we also provide a cross-layer routing protocol design in order to reduce the data queue processing time and to send out the priority data at both network and MAC layer.