In Optical Burst Switching (OBS) networks, when contention occurs at an intermediate node, two or more bursts that are in contention can be dropt because a forwarding path reservation is not made for a burst. This is the reason why one of the critical design issues in OBS networks is finding ways to minimize burst dropping resulting from resource contention. In this paper, we propose a configuration management policy based on an operation cost model developed according to network status information which relates to guaranteeing Quality of Service (QoS). Also, we develop the criteria for the configuration management by providing the alternate path using bounded range of the sensitivity of this cost model. Finally, throughout the theoretical and experimental analysis, we can obtain that our proposed scheme has good performance in an aspect of blocking rate and outperforms the conventional scheme in complexity as results.