Internet的迅速发展和用户需求的不断增长，使得Internet上新业务的提供成为瓶颈。主动网络的目的是让网络有计算能力，使得灵活加载新业务成为可能，这为Internet的发展开辟了新的方向。文章首先介绍了主动网络的概念与意义，然后给出了主动节点的结构以及密封囊的传输、加载和执行机制，介绍了国内外研究动态与进展。最后提出主动网络的一个实际应用。 The rapid development of the Internet and the ever-increasing demand of users make the provision of new services on the Internet a bottleneck. The purpose of the active network is to make the network have computing power, making it possible to flexibly load new services, which opens up a new direction for the development of the Internet. The article first introduces the concept and significance of active networks, and then gives the structure of active nodes and the transmission, loading and execution mechanism of sealed capsules. The research developments and developments at home and abroad are introduced. Finally put forward a practical application of active network.