A Quasi-Static Optoelectronic ATM Switch

在过去的十年中，光纤的几乎无限的带宽已经引起了数据传输速度的巨大增长，从而刺激了高要求的Gb/s多媒体服务，如远程学习和视频会议。 ATM作为传输宽带综合业务数字网（BISDN）应用的一种有前途和有效的技术已被ITU-T所接受。 基于研究者提出的路径交换的概念，他们提出了一种Tb/s多播ATM交换机结构，该结构将电子交换模块与准静态受控光互连网络（OIN）互连。 OIN中的路由是预先确定的，以避免逐个时隙的处理，并在虚拟路径级上提供灵活的交换容量。 周围的电子交换模块支持组播、快速动态路由和统计复用，以补偿OIN中的准静态路由，从而实现总共Tb/s的交换容量。 这种准静态交换结构将Tb/sATM交换机的设计简化为具有特定功能的Gb/s交换模块：电子组播输入输出模块和光中心互连模块，这些模块在现有技术条件下都是可行的。 首先，研究人员将开发一种更新机制，用于调整中期路线模式以适应交通变化。 时间复杂度和性能之间的权衡将被调查。 其次，他们将根据我们提出的OIN确定光学器件的要求，以有效地控制串扰和功率预算。 此外，他们还将研究在多播电子交换模块中执行输出竞争解决的几种方法：为每种方法制定一个具有成本效益的设计，研究吞吐量，信元延迟和丢失率方面的性能，并最终确定具有高性能和合理结构复杂性的最佳方法。

The virtually unlimited bandwidth of optical fibers has caused tremendous increase in data transmission speed during the past decade, thereby stimulating high demanding Gb/s multimedia services such as distance learning and video conferencing. ATM has been accepted by ITU-T as a promising and efficient technique of transporting Broadband Integrated Services Digital Network (BISDN) applications. The new challenge lies in the deployment of Tb/s multicast ATM switches tomeet the exponential growth of multimedia and internet traffic.Based on the concept of the researcher's path switching, they propose a Tb/smulticast ATM switch architecture that interconnects electronic switch modules with a quasi-static controlled optical interconnection network (OIN). Routing in the OIN is predetermined to avoid slot-by-slot processing and to provide flexible switching capacity on virtual pathlevel. The surrounding electronic switch modules support multicasting, fast dynamic routing and statistical multiplexing to compensate the the quasi-static routing in the OIN to achieve totally a Tb/s switching capacity. This quasi-static switching architecture simplifies the design of a Tb/s ATM switch to specially featured Gb/s switch modules: the electronic multicast input and output modules and optical central interconnection, which are all feasible with existing technology.The future research plan includes three aspects. First, the researchers will develop an updating mechanism for readjusting the middle-stage route pattern to adapt the traffic change. The tradeoff between time complexity and performance will be investigated. Secondly, they will identify the requirement of the optical devices to effectively control the crosstalk and the power budget based on our proposed OIN. Inaddition, they will investigate several approaches of performing output contention resolution within multicast electronic switch modules: work out a cost-effective design for each approach, study the performance in terms of throughput, cell delay and loss rate, and finally identify the best approach that has high performance and reasonable construction complexity.