Optical burst switching (OBS) is a promising technique for next-generation optical switching networks which attempts to address the problem of efficiently allocating resources for bursty traffic. In traditional OBS, an entire burst is discarded when all output wavelengths are engaged at the arrival instant of the burst. A critical design issue in OBS is how to reduce burst dropping probability as a result of resource contention. This paper proposes new core node architecture to provide a combined impact for an effective scheduling algorithm that improves burst loss rate and utilization in OBS switches. The new design provides an effective optical burst switching for variable-length bursts with low complexity compared to several existing scheduling algorithms. A combined contention resolution approach of wavelength reassignment capability and limited delay is used.