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Abstract : Balancing the communication traffic between multiple lightpaths, using particular RWA protocol for all class-of-traffics, or a combination of both leads to the degradation of the WDM network performance. Hence for better performance of WDM network, in this paper we designed and analyzed an advanced centralized priority based RWA protocol (ACPR) for WDM networks in which appropriate RWA methodologies are used depending on the priority and speed of the incoming traffics to identify the optimal primary and backup lightpaths. In addition protocol uses two Centralized Management System CMS1 and CMS2 to reduce the network performance bottleneck problem by sharing the work and also if any failure occurs to either of CMS the other CMS take over its responsibilities. Whenever a request comes, it is placed in queue. Then CMS takes alternative requests from the queue. Then CMS identifies the traffic class depending on their priority and speed as high priority high speed (HPHS), high priority low speed (HPLS), low priority high speed (LPHS) and low priority low speed (LPLS). CMS uses appropriate RWA methodologies as per incoming requests to identify the optimal light paths like for HPHS it uses number of free wavelengths, for HPLS it uses number of free wavelengths and also tries for grooming, for LPHS it uses number of free wavelengths and for LPLS it uses number of free wavelengths and also tries for grooming. In this RWA protocol in order to give more importance to high priority request the available wavelength set is divided into three subsets, called P set of higher order wavelengths, C set of common wavelengths for high priority and low priority and remaining S wavelengths used as a backup wavelength for control signals. In case of any failure in control signal wavelengths, S set of backup wavelengths can be used. Protocol also finds an optimal light path for high priority request using wavelengths from subset C, else finds out using wavelengths from subset P. Optimal light path for low priority traffics are found by only using wavelengths from subset C. Further for survivability of connections in the case of failure the backup light path is allocated. The selection of backup light path is done in such a way that there is no shared link between the primary and backup light path. By simulation results, we have shown that high priority requests have low blocking probability in comparison to low priority requests. This electronic document is a live template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.