Network construction of digital communication includes two main parts. First, construction of digitalexchange network;
数据通信的网络建设工程包括两个主要内容：第一，构建数据交换网络。
2
We'll introduce the technology of designing the software system of the HJD-500/1000 digitalexchange using programming language C on TP-86D single-board computer.
本文介绍在设计HJD-500/1000型数字交换机软件系统时在单板机环境下使用C语言的实现技术。
3
This digital identity can then be used to exchange text securely by encryption using the key pair.