p4-DXR

To craete a topology in Mininet and run our P4 program as a switch, we make use of the tool P4-Utils. It not only provides a script that automatically install all dependencies, it also provides a Python module, which defines and runs the Mininet topology with P4 programs integrated, and a CLI command that takes in a JSON file as its input to realize the same functionality. The detail of P4-Utils can be found at https://github.com/nsg-ethz/p4-utils#requirements.

Our logic of preprocessing is located in preprocess.py. p.py includes codes to start preprocessing and generate control plane commands for our P4 program. Our P4 implementation of the DXR algorithm is in dxr.p4. To test our implementation, we define and run the Mininet topology in rundxr.py.

Here are the steps to run our code:

1. Put bgptable.txt under the same directory as all other source files.
2. Run python3 p.py to preprocess the input prefixes and generate control plane commands for our p4 program; all commands will be written to file cmd1.txt (Note that we have already generated all commands in cmd1.txt and pushed the file to the repository, so it is ok to skip step 2).
3. Run sudo python3 rundxr.py to start the defined topology in Mininet. After the running, it enters the command line of Mininet.
4. Run Mininet commands to test the connections among hosts (for example pingall).
5. The log of the switch implemented by our P4 program is located in ./log/p4s.s1.log. The pcap directory is ./pcap , and the files can be checked with tcpdump command.