[{"title":"( 5 个子文件 5.67MB ) 交换技术 课件 《现代交换原理与通信网技术》","children":[{"title":"交换技术","children":[{"title":"信令系统.ppt <span style='color:#111;'> 1.76MB </span>","children":null,"spread":false},{"title":"第三章 数字程控电话交换与电话通信网.ppt <span style='color:#111;'> 3.20MB </span>","children":null,"spread":false},{"title":"ATM交换.ppt <span style='color:#111;'> 960.00KB </span>","children":null,"spread":false},{"title":"第一章 概述.ppt <span style='color:#111;'> 766.00KB </span>","children":null,"spread":false},{"title":"第二章 交换网络.ppt <span style='color:#111;'> 568.00KB </span>","children":null,"spread":false}],"spread":true}],"spread":true}]