Abstract: In recent years, knowledge management has become an increasingly important topic in the fields of both information technologies and business management. Many organizations have formally set up knowledge management as a pressing task in their current business objectives. This paper intends to discuss some important concepts in the domain of knowledge management, such as Explicit and Tacit Knowledge, Community of Practice and Ontology, etc. It also summarizes some applications of modern informatio

Key words: SDH(Synchronous Digital Hierarchy), access networks, theory, application

摘要： 本文系统而全面的介绍了光城域胺入网中II'OverSDH技术的基本原理，以及IPOverSDH技术在接入网中 的应用，分析了把SDH系统应用在接入网中需要解决的问题，并给出了一个比较完整的高速公路基层用户的接人 实例

关键词: 光同步数字传输网, 接入网, 原理, 应用