In this paper, we numerically explore the potential of multiuser optical communication system based on generalized and complete synchronization. The two mutually delayed coupled master lasers in the transmitter and receiver sides are completely synchronized to provide the identical driving signal. Different slave lasers are coupled to the driving signal in a master-slave configuration and thus display generalized synchronization between the master laser and slave lasers in both sides, while the corresponding slave lasers in the transmitter and receiver are completely synchronized due to the identical driving signal and their identical device parameters. We show the capacity of the proposed system for encoded message transmission in a multiuser chaos-based communication scenario.