pifus - A Predictable Interface for a User Space IP Stack

pifus is an interface for the lwIP stack. It is based on a completion I/O model and therefore allows async I/O using lwIP with an API similar to BSD sockets.

pifus supports predictability features, such as setting priorities for sockets so that real-time traffic can be prioritized.

pifus furthermore allows multiple processes to use the lwIP stack simultaenously.

The main code contributions of pifus can be found in the api folder (contains the interface for the applications) and in the lwip/custom folder (contains the backend logic).

The theoretical groundwork and benchmark results can be found in the Master Thesis located in the repository root.

Build

mkdir build && cd build
cmake ..
make

Then, the lwIP stack with the pifus backend is built in lwip/custom/stack/stack.

Usage

Applications that want to use the stack may use the pifus library. See api/benchmarks for example applications.

Use the environment variable PRECONFIGURED_TAPIF=tapX to set the TAP interface that the stack should use.

The stack will then automatically set its IP to 192.168.1.200. This is currently hard coded and can only be changed in the source code.