Lemur Compiler

Lemur is a flexible and high-performance packet processing framework that meets SLOs in cross-platform NFV.

Lemur works as a cross-platform compiler. It parses NF chains from a user-level specification, and considers all available hardware resources to generate an placement scheme for NFs. In Lemur, NFs from the same NF chain may be placed at different platforms. Lemur considers the fundemental tradeoff between performance and programmability to achieve a higher throughput.

Features

(1) Flexible configuration of multiple network service chains
(2) Efficient heuristic algorithm for hardware deployment decision
(3) Involve 'minimum bounce', 'HW preferred', 'SW preferred', 'Greedy' algorithms as comparison altermatives
(4) Fast deployment on heterogeneous hardware (automatic code generation for P4 and BESS code)

Build Instructions

Dependencies

(1) Clone this repo

$ git clone https://github.com/USC-NSL/Lemur.git

(2) Check the Python version Lemur is tested with Python 2.7.12 + pip 20.2.4.
Please make sure you have the correct Python + pip version.
We recommend using pyenv (https://github.com/pyenv/pyenv) to manage your Python local env.
Also, you may refer to the comment section in install_deps.sh to install pyenv, Python, and pip properly.

(2) Install dependencies

$ ./install_deps.sh

Required dependencies:

• Numpy 1.15.4
• paramiko 1.16.0
• Pexpect 4.6.0
• termcolor 1.1.0

(3) Get Gurobi License
Please follow the instructions in /src folder to get your Gurobi license

Note: according to some Lemur users, Lemur compiler may not work properly under academic licence outside the US.

Configuring Lemur

(1) Visit the src directory and define your service chain configuration file in the user_level_example directory
Here is an example of Lemur user-level configuration script.
(Please check chain_1.conf)

AESCBC()-> VLANPush()->IPv4Forward()

(2) Configure your SLOs, hardware setting and profiled number
device.txt: NIC information for your BESS server
module_data.txt: Profiled CPU cycles for each BESS modules on your BESS server
max_delay.txt: Your max delay setting for your service chains. One row contains only one delay number for a service chain. The row order matches with the service chain order.
chain_rate.txt: Your [min, max] throughput settings for your service chains. One row contains one [min, max] throughput requirement for a service chain. The row order macthes with the service chain order.

Running Lemur

(1) Run Lemur compiler with heuristic algorithm in src directory
Let's assume that you are trying to compile chain_0_1_2_3.conf. You will run the Lemur compiler by typing the following.

$ python lemur_heuristic_compiler.py -f chain_0_1_2_3

The Lemur compiler will output two files. nf.p4 is the final P4 code that incorporates all P4 NF nodes, while intel_nic1.bess is the final BESS configuration script that includes all BESS modules. The naming of BESS script is based on the nic information provided in device.txt.

(optional) If you would like to compare with the brutal force algorithm and other alternatives, type the following in src directory.

$ python lemur_compiler.py -f chain_0_1_2_3

The default algorithm is the brutal force algorithm. To change to other alternatives, you can set -m {$MODE_NUMBER} to switch. For more detail, please use -h to view options.

(2) Download P4 code and BESS script to your hardware and compile. Due to NDA regulations, please directly contact your PISA switch vendor for compilation problem. Note that you will still need to register table entries for your traffic to guarantee service chains are operated to your traffic.

Additional Instructions

For Lemur to properly check stage constraints, you can leverage /src/connect.py file to set up your ssh connection to your PISA switch. We have removed our testbed's information in the script, so please change the setting for your experiment setup.

MILP Problem Formulation

We include our MILP problem formulation in MILP_formulation.pdf.