| Summary: | 碩士 === 國立臺灣大學 === 電信工程學研究所 === 91 === Abstract
In this paper, a multi-plane cross-bar switch called NTU-II switch is proposed and implemented. This switch has the following features:
1) Asynchronous operation mode
2) Modular design to achieve high scalability
3) Handling Ethernet variable length packet directly without fragmentation and recombination.
4) Self Routing without central controller
5) Non-blocking
Compared to the NTU-I switch proposed previously, there are two major improvements. One is the use of request-polling handshaking protocol to transfer packets between internal circuits. It reduces the transmission latency in the switch. The other is channel grouping to partition whole switch into smaller sub-switches. It makes the implementation easier when we want to increase the switch I/O ports while hardware resources such as I/O pins, memories are limited. The former builds a simple interface between circuits, and the latter makes modular design more feasible.
Because there are four planes in a sub-switch, simulation based on mathematical model shows that the throughput can reach 100% in geometric arrival, uniform distribution traffic. This result shows that the proposed switch compares favorably with the output-queue switch.
The NTU-II switch is composed of preprocessors, sequencers, switching elements, and the output memory management units. An 8x8 switch with line rate 1 Gb/s is implemented using FPGA ( xc2v3000-4 fg676, Xilinx Corp. ).
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