Abstract: Adopting multi-granularity switching in WDM optical networks can dramatically reduce the size of optical cross-connect, which saves the cost of building and maintaining of networks. In this paper, the structures of multi-granularity optical cross-connect in some previous works are introduced, and two kinds structure of multi-granularity optical cross-connect are proposed. The performances of different structures are analyzed and compared in terms of size of switching box, switching and grooming abilities, and the blocking performance.

Key words: multi-granularity switching, OXC, MG-OXC, traffic grooming

摘要： 在WDM光网络中引入多粒度交换可以有效地减小交换节点中交叉连接矩阵的规模，从而大大降低网络的成本。在介绍现有的多粒度交换节点结构的基础上，提出了2种两层的交换结构。详细分析比较了不同结构的内部交换矩阵规模、交换和流量疏导能力，并通过比较可实现的交换组合数目分析了其阻塞性能。

关键词: 多粒度交换, 光交换节点（OXC）, 多粒度光交换节点（MG-OXC）, 流量疏导