【作者】 张少堂；

【导师】 胡卫生；

【作者基本信息】 上海交通大学 ， 通信与信息系统， 2011， 硕士

【摘要】 互联网业务的飞速发展给现代网络通信提出了新的挑战,尤其是光纤通信的应用极大提高了通信网数据传输的速率,但是交换容量的相对滞后问题也越来越明显。光交换技术的提出加快了核心网的发展,它主要包括光路交换(OCS)、光突发交换(OBS)和光分组交换(OPS)三种光交换技术。其中,光分组交换(Optical Packet Switching, OPS)的基本交换单位是光分组,它有较小交换粒度、高带宽利用率、大容量、高数据速率和光包格式透明等特点,另外它适用于突发性较强的业务,因此光分组交换技术成为了未来光网络发展的一个重要方向。本文作者所在实验室依托自身优势开展了国家自然科学基金重点项目“光分组交换关键技术与实验平台”(简称McTOPS),在该项目的实施过程中,本文作者承担了光分组交换网核心节点硬件方面的设计和实现,主要包括核心节点交换控制平台的设计和实现、核心节点光标记提取电路的设计和实现、核心节点交换矩阵的设计和实现,另外还编写了光分组交换逻辑供硬件设计参考。本文首先介绍了光分组交换网络的发展现状和前景,然后介绍光分组交换网络的整体架构,并将时隙光分组交换网络和非时隙光分组交换网分别加以介绍。针对本文作者在McTOPS项目中承担的工作,重点介绍了光分组交换网络中的几种关键技术,包括光标记技术、光分组报头处理技术和光分组交换的冲突解决技术等。结合McTOPS项目,介绍了光分组交换网络中的两种节点:边缘节点和核心节点,重点阐述了它们的作用和技术上的难点。其次,本文介绍了作者在国家自然科学基金重点项目“光分组交换关键技术与实验平台”(简称McTOPS)中所承担的主要工作,主要讨论了光分组交换网络中核心节点的硬件设计和实现,具体包括核心节点交换控制平台、核心节点光标记提取电路和核心节点SOA光交换矩阵的设计和实现。另外,本文作者还使用Verilog语言编写了核心节点交换逻辑程序。对于上述各部分的硬件平台,本文作者都做了验证和结果分析。第三,本文介绍了本文作者提出的一种SOA交换矩阵的功耗优化方法,主要针对SOA的偏置电流进行优化,可以有效的降低SOA交换矩阵的功耗。如果OPS网络中的负载特性在各端口体现出不均衡性,则该功耗优化方法还能够更显著地提高功耗优化效率。最后,总结全文的研究工作,还对光分组交换网络中核心节点的设计做了展望,并指出了进一步提高SOA交换矩阵功耗优化效率的方法。更多还原

【Abstract】 With the rapid development of Internet and increasing transmission data rates, switching capacity is still one of primary bottlenecks of the network. Optical switching technology includes optical circuit switching (OCS), optical burst switching (OBS) and optical packet switching (OPS). Among them, OPS technology has advantages of finer transmission and switching granularity, much flexibility and higher bandwidth utilization, and is so regarded as one of the evolution solution of future all-optical network.The laboratory where the author works has undertaken several research projects on OPS technology. This thesis summaries what the authors have done in NSFC-funded Key Project of "Multicasting capable Testbed of Optical Packet Switch (McTOPS)". The scope of this thesis focuses on the key technologies of OPS networks, including optical packet switch controlling platform, optical label extracting circuits and optical switching fabric based on Semiconductor Optical Amplifier (SOA).Firstly, the generic architecture of OPS networks and the differences between synchronous and asynchronous OPS networks are introduced. The key technologies such as the label extracting, label processing and contention resolution are respectively introduced. The general functions and structures of edge node and core node are summarized, and we also discuss these two kinds of nodes in McTOPS.Secondly, implementation scheme of core node in the McTOPS project based on FPGA and SOA switching fabric is promoted. We focus on the optical label extracting circuit, optical packet switching controlling platform and SOA based optical packet switching fabric. Moreover, optical packet switching algorithm of core node in McTOPS is presented.Thirdly, we propose a scheme to optimize the power consumption in Optical Packet Switching (OPS) node based on Semiconductor Optical Amplifiers (SOA). This optimization algorithm is used to reduce bias current of each output SOA in switching fabric. By simulation, it demonstrates that the scheme as proposed can reduce switching fabric power consumption by about 10%, and we also get that the efficiency will be larger with unbalanced traffic load.Finally, we conclude the thesis with the outlook on the future research and implementation both in core node design and optimization of power consumption of switching array.更多还原