说明：  本文叙述了lwIP的设计与实现。叙述了协议实现及子系统中所使用的算法和数据结构如存储和缓冲管理系统。还包括LWIP API的参考手册和使用LWIP 的一些代码例子。
(This paper describes the design and implementation of lwIP s. And the protocol described algorithms and data structures used in the subsystem, such as a buffer storage and management system. Also includes LWIP API reference manual and use some code examples LWIP s.)