A Frame-Based Architecture with Shared Buffers for Slotted Optical Packet Switching

Because of the lack of random access memory in optical domain, optical buffering implemented by fiber delay lines is currently a main way. Typical optical buffering architecture falls into two categories: feed-forward and feedback buffering. Both have advantages and disadvantages. In this paper, we propose an effective hybrid buffering architecture based on output-buffered feed-forward and feedback shared buffering architecture. The proposed architecture employs feed-forward output buffers to connect packets to form a variable-length frame, and employs a feedback shared buffer with a large storage frame to handle frames behind feed-forward output buffers. This scheme uses a frame concept to reduce the control complexity and increase the buffer depth. Our simulation results show that the proposed architecture improves the switch performance and outperforms an existing hybrid buffering architecture, partially shared buffering architecture, in terms of packet loss probability.