A node architecture for optical multicast contention resolution and its scheduling strategy

作者：Liu Huan Lin^*; Hu Ting; Hu Xiao Hui; Chen Yong; Huang Sheng

来源：Journal of Optoelectronics - Laser, 2014, 25(11): 2108-2113.

• Contention resolution
• Fiber delay line (FDL)
• Multicast scheduling
• Optical multicast
• Packet loss probability
• Proposed architectures
• Scheduling strategies
• Scheduling techniques

Optical packets'contention resolution in core node is a key to realizing the all-optical multicast packet switching. A novel node architecture is proposed to resolve contention for optical multicast in this paper. In the proposed architecture, output shared network coding module and Fiber Delay Line Loop Shared Feedback Buffering (FDL-LSFB) module are designed in the node for contention resolution. As for the network coding module, XOR network coding is used as the first contention resolution method. All-optical logic XOR gates are used to encode conflicting multicasts and exchange the carrier wavelength of the encoded multicast to avoid wavelength contention. The FDL-LSFB module, consisting of sub-switches and FDL buffer groups, is designed as the second contention resolution method. In FDL-LSFB module, FDL buffer groups are connected by sub-switches that guarantee the conflicting multicasts to enter or leave the FDL-LSFB module from any sub-switch. The FDL-LSFB module uses only a few FDLs and provides large buffering memories to resolve the multicast time contention with high FDL utilization. Moreover, the Minimum length Cascaded Buffer Scheduling Technique (MLCBST) is brought forward to schedule the FDL-LSFB module. Based on the MLCBST, the total multicast scheduling strategy for optical multicast is designed for the proposed node architecture. The simulation results show that the proposed node architecture and the scheduling strategy have an obvious effect in reducing packet loss probability (PLP) and decreasing the average delay.

• 出版日期2014