| INTRODUCTION |
| |
| lwIP is a small independent implementation of the TCP/IP protocol |
| suite that has been developed by Adam Dunkels at the Computer and |
| Networks Architectures (CNA) lab at the Swedish Institute of Computer |
| Science (SICS). |
| |
| The focus of the lwIP TCP/IP implementation is to reduce the RAM usage |
| while still having a full scale TCP. This making lwIP suitable for use |
| in embedded systems with tenths of kilobytes of free RAM and room for |
| around 40 kilobytes of code ROM. |
| |
| FEATURES |
| |
| * IP (Internet Protocol) including packet forwarding over multiple |
| network interfaces |
| * ICMP (Internet Control Message Protocol) for network maintenance |
| and debugging |
| * UDP (User Datagram Protocol) including experimental UDP-lite |
| extensions |
| * TCP (Transmission Control Protocol) with congestion control, RTT |
| estimation and fast recovery/fast retransmit |
| * Specialized API for enhanced performance |
| * Optional Berkeley socket API |
| |
| LICENSE |
| |
| lwIP is freely available under a BSD license. |
| |
| DEVELOPMENT |
| |
| lwIP has grown into an excellent TCP/IP stack for embedded devices, |
| and developers using the stack often submit bug fixes, improvements, |
| and additions to the stack to further increase its usefulness. |
| |
| Development of lwIP is hosted on Savannah, a central point for |
| software development, maintenance and distribution. Everyone can |
| help improve lwIP by use of Savannah's interface, CVS and the |
| mailing list. A core team of developers will commit changes to the |
| CVS source tree. |
| |
| The lwIP TCP/IP stack is maintained in the 'lwip' CVS module and |
| contributions (such as platform ports) are in the 'contrib' module. |
| |
| The CVS main trunk is the stable branch, which contains bug fixes and |
| tested features. The latest stable branch can be checked out by doing: |
| cvs -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip login |
| cvs -z3 -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip co lwip |
| |
| The 'STABLE' tag in the stable branch will represent the most stable |
| revision (which may be somewhat older to protect us from errors |
| introduced by merges). This 'STABLE' tagged version can be checked out |
| by doing: |
| cvs -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip login |
| cvs -z3 -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip co -r STABLE lwip |
| |
| The 'DEVEL' branch is the active development branch, which contains |
| bleeding edge changes, and may be instable. It can be checkout by doing: |
| cvs -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip login |
| cvs -z3 -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip co -r DEVEL lwip |
| |
| The current contrib CVS tree can be checked out by doing: |
| cvs -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip login |
| cvs -z3 -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/lwip co contrib |
| |
| Last night's CVS tar ball can be downloaded from: |
| http://savannah.gnu.org/cvs.backups/lwip.tar.gz |
| |
| The current CVS trees are web-browsable: |
| http://savannah.nongnu.org/cgi-bin/viewcvs/lwip/lwip/ |
| http://savannah.nongnu.org/cgi-bin/viewcvs/lwip/contrib/ |
| |
| Submit patches and bugs via the lwIP project page: |
| http://savannah.nongnu.org/projects/lwip/ |
| |
| |
| DOCUMENTATION |
| |
| The original out-dated homepage of lwIP and Adam Dunkels' papers on |
| lwIP are at the official lwIP home page: |
| http://www.sics.se/~adam/lwip/ |
| |
| Self documentation of the source code is regularly extracted from the |
| current CVS sources and is available from this web page: |
| http://www.nongnu.org/lwip/ |
| |
| Reading Adam's papers, the files in docs/, browsing the source code |
| documentation and browsing the mailing list archives is a good way to |
| become familiar with the design of lwIP. |
| |
| Adam Dunkels <adam@sics.se> |
| Leon Woestenberg <leon.woestenberg@gmx.net> |
