Over the last few years, the interest for connecting computers and computer supported devices to wireless networks has steadily increased. Computers are becoming more and more seamlessly integrated with everyday equipment and prices are dropping.
Description of LWIP
At the same time wireless networking technologies, such as Bluetooth and IEEE 802.11b WLAN , are emerging. This gives rise to many new fascinating scenarios in areas such as health care, safety and security, transportation, and processing industry. Small devices such as sensors can be connected to an existing network infrastructure such as the global Internet, and monitored from anywhere.
The Internet technology has proven itself flexible enough to incorporate the changing network environments of the past few decades. While originally developed for low speed networks such as the ARPANET, the Internet technology today runs over a large spectrum of link technologies with vastly different characteristics in terms of bandwidth and bit error rate. It is highly advantageous to use the existing Internet technology in the wireless networks of tomorrow since a large amount of applications using the Internet technology have been developed.
Also, the large connectivity of the global Internet is a strong incentive.Since small devices such as sensors are often required to be physically small and inexpensive, an implementation of the Internet protocols will have to deal with having limited computing resources and memory. This report describes the design and implementation of a small TCP/IP stack called lwIP that is small enough to be used in minimal systems.As in many other TCP/IP implementations, the layered protocol design has served as a guide for the design of the implementation of lwIP.
Each protocol is implemented as its own module, with a few functions acting as entry points into each protocol.