This work presents studies of an interconnected Multi-Ring Network (MRN) architecture in which a Metropolitan Access (MA) Ring is interconnected by a Metropolitan Core (MC) Ring. The interconnection of MC and MA networks is made via hub node that is in charge of the synchronization between them. The synchronization of two rings while assuring the traffic routed efficiently from the MA to the MC networks is the major problem in this architecture. To solve this problem, we propose a new mechanism called Common-Used Timer Mechanism (CUTM) inspired from CoS-Upgrade Mechanism (CUM) to create optical packets well filled in the hub. CUTM is developed and also integrated as a module to the software Network Simulator 2 (NS2), to simulate the behavior of the MRN considered. We compare the performance of this mechanism with the opportunistic one. The results have shown that, compared to existing solutions, the CUTM enhances the network throughput, packet filling creation ratio and optimizes the use of resources. Also, it solves the synchronization problem