LWIP是TCP/IP协议栈的一种实现。LWIP的主要目的是减少存储器利用量和代码尺寸，使LWIP适合应用于小的、资源有限的处理器如嵌入式系统。为了减少处理器和存储器要求，lwIP可以通过不需任何数据拷贝的API进行裁减。

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。-LWIP is TCP/IP Protocol Stack A. LWIP the main purpose is to reduce memory utilization and code size, LWIP suited for small, limited resources such as the processor embedded system. In order to reduce the processor and memory requirements, lwIP can copy data without any of the API for the reduction. This paper describes the lwIP Design and Implementation. Describes the protocol and subsystems used in the algorithm and data structure such as memory and buffer management system. LWIP API also includes a reference manual and use LWIP some code examples.