本文描述了E1000类网卡的收发包原理，详细介绍了BD环的原理，形成及使用过程。对网卡驱动开发，网卡性能优化等有直接的帮助。-This paper describes the the E1000 NIC transceiver package principle, details of the the BD ring the principle, formation and use process. Drive the development of the network card, network card performance optimization direct help.