P4-MNA: P4 Implementation of the MPLS Network Actions (MNA) Framework

• Overview
• Installation & Start Instructions
  • Data plane
  • Control plane
• Utils
  • Wireshark Dissector
  • MNA Framework Python Libary
• Cite

Overview

This repository contains the source code of MPLS Network Action (MNA) implementations in P4 for the Intel Tofino 2 switching ASIC as introduced by the MPLS Working Group. The MNA in-stack data (ISD) implementation features

• A Readable Label Depth (RLD) of 51 LSEs.
• Parsing and processing of two maximum-sized NAS (select-scoped and HBH-scoped) at an LSR
• An exemplary network action for packet loss measurement using the alternate-marking-method (AMM) (based on draft-cx-mpls-mna-inband-pm-05)
• An exemplary network action for bandwidth reservation with network slicing (based on draft-li-mpls-mna-nrp-selector-02)

In the future, a PSD implementation will be added to this repository.

Further, this repository contains a library to build packets in the MNA framework, and a Wireshark dissector to visualize them.

Installation & Start Instructions

Data Plane

Go to P4-Implementation and compile P4-MNA via make compile. This compiles the program and copies the resulting configs to the target directory.

Afterwards, start P4-MNA via make start.

This requires a fully setup SDE with set $SDE and $SDE_INSTALL environment variables.

Control Plane

The controller is written in Rust and can be started via cd Local-Controller && cargo run. This will build and start the control plane.

Make sure to configure physical ports of your device and add MPLS forwarding rule. An example is given in main.rs.

Utils

Wireshark Dissector

Place the utils/wireshark/mna_wireshark.lua file in your Wireshark lua plugins folder, e.g., in /usr/lib/x86_64-linux-gnu/wireshark/plugins (from 'About Wireshark' --> 'Folders').

Note: This plugin replaces the MPLS dissector of Wireshark. It is intended for analysis and debugging of MNA traffic only.

Example

MNA Framework Python Library

The file utils/scapy/MNA.py contains a library for building MNA packets. See utils/scapy/send_mna_packet.py for examples using the MNA library and sending packets using the scapy library.

Example Output of an MNA frame

| LSE Label: 50, BoS: 0 |, 0x32e3f
| LSE Label: 4, BoS: 0 |, 0x4e40
|  Initial opcode: 64, Scope: SELECT, NASL: 4 BoS: 0 |, 0x80000404
|     Subsq. opcode: 64, NAL: 0 BoS: 0 |, 0x80000400
|     Subsq. opcode: 64, NAL: 0 BoS: 0 |, 0x80000400
|     Subsq. opcode: 64, NAL: 0 BoS: 0 |, 0x80000400
|     Subsq. opcode: 64, NAL: 0 BoS: 0 |, 0x80000400
| LSE Label: 60, BoS: 0 |, 0x3ce3f
| LSE Label: 70, BoS: 0 |, 0x46e3f
| LSE Label: 4, BoS: 0 |, 0x4e40
|  Initial opcode: 64, Scope: HBH, NASL: 4 BoS: 0 |, 0x80000a04
|     Subsq. opcode: 64, NAL: 1 BoS: 0 |, 0x80000401
|          Data entry BoS 0 |, 0x80000000
|     Subsq. opcode: 64, NAL: 0 BoS: 0 |, 0x80000400
|     Subsq. opcode: 64, NAL: 0 BoS: 0 |, 0x80000400
| LSE Label: 80, BoS: 0 |, 0x50e3f
| LSE Label: 90, BoS: 0 |, 0x5ae3f

MNA Evaluation

The directory evaluation contains files that script traffic generation using the traffic generator P4TG which was used for the evaluation in the paper.

Citing P4-MNA

If you use P4-MNA in any of your publications, please cite the following paper:

• F. Ihle and M.Menth, MPLS Network Actions: Technological Overview and P4-Based Implementation on a High-Speed Switching ASIC, preprint, Feb. 2025, (under submission)