城域灵活细粒度OTN网络节点设计与实现(特邀)OA

[Objective]In the era of Fifth-Generation Mobile Communication(5G)and cloud computing,the volume of transmit-ted data has increased rapidly,and service patterns become fine-grained and fragmented.Although traditional Optical Transport Network(OTN)systems perform well in large-granularity and long-haul backbone transmission,their fixed and coarse granulari-ty limits their efficiency in supporting flexible small-granularity services at the metropolitan access layer,resulting in unnecessary bandwidth waste.Consequently,enhancing traditional OTN architectures to efficiently support flexible fine-granularity services has become an active research topic.In this work,an OTN network node capable of supporting flexible fine-grained metropolitan services is designed and implemented.[Methods]First,fine-granularity service grooming at the Optical Service Unit(OSU)lev-el is implemented,enabling flexible cross-grooming and bandwidth adjustment for small-granularity services.Second,to address the throughput degradation observed in small-packet Ethernet transmission,the conventional 64b/66b encoding scheme is opti-mized by detecting consecutive idle frames and suppressing the generation of invalid encoding blocks,thereby improving through-put under low-load conditions.Finally,system performance,including throughput,latency,and packet delay variation,is evalu-ated under different Ethernet rates and frame-size configurations.[Results]Experimental results show that,at a line rate of 10 Gbit/s,the maximum error-free throughput reaches 94.9%,while the minimum supported error-free rate is 2 Mbit/s.During cross-grooming and bandwidth adjustment,data transmission remains continuous and lossless.The minimum system latency is approximately 10 μs,and packet delay variation is limited to within 250 ns.Compared with conventional OTN systems,the pro-posed solution supports lossless dynamic bandwidth adjustment and fine-granularity service provisioning at the metropolitan edge,achieving improved bandwidth utilization and service flexibility.[Conclusion]A compact metropolitan OTN-OSU network node based on OSU technology is designed and implemented on a domestic Field-Programmable Gate Array(FPGA)platform.Ex-perimental verification demonstrates its feasibility as a flexible fine-granularity OTN network node for metropolitan applications.