Plenum Byzantine Fault Tolerant Protocol

Plenum Byzantine Fault Tolerant Protocol

Plenum makes extensive use of coroutines and the async/await keywords in Python, and as such, requires Python version 3.5.0 or later. Plenum also depends on libsodium, an awesome crypto library. These need to be installed separately. Read below to see how.

Plenum has other dependencies, including the impressive RAET for secure reliable communication over UDP, but this and other dependencies are installed automatically with Plenum.

Installing Plenum

pip install plenum

From here, you can play with the command-line interface (see the tutorial)...

Note: For Windows, we recommended using either cmder or conemu.


...or run the tests.

git clone
cd plenum
python -m plenum.test

Details about the protocol, including a great tutorial, can be found on the wiki.

Installing python 3.5 and libsodium:


  1. Run sudo add-apt-repository ppa:fkrull/deadsnakes

  2. Run sudo apt-get update

  3. On Ubuntu 14, run sudo apt-get install python3.5 (python3.5 is pre-installed on most Ubuntu 16 systems; if not, do it there as well.)

  4. We need to install libsodium with the package manager. This typically requires a package repo that's not active by default. Inspect /etc/apt/sources.list file with your favorite editor (using sudo). On ubuntu 16, you are looking for a line that says deb xenial main universe. On ubuntu 14, look for or add: deb trusty main and deb-src trusty main.

  5. Run sudo apt-get update. On ubuntu 14, if you get a GPG error about public key not available, run this command and then, after, retry apt-get update: sudo apt-key adv --keyserver --recv-keys B9316A7BC7917B12

  6. Install libsodium; the version depends on your distro version. On Ubuntu 14, run sudo apt-get install libsodium13; on Ubuntu 16, run sudo apt-get install libsodium18

  7. If you still get the error E: Unable to locate package libsodium13 then add deb trusty main and deb-src trusty main to your /etc/apt/sources.list. Now run sudo apt-get update and then sudo apt-get install libsodium13


  1. Run sudo yum install python3.5

  2. Run sudo yum install libsodium-devel


  1. Go to and from the "Downloads" menu, download the Python 3.5.0 package (python-3.5.0-macosx10.6.pkg) or later.

  2. Open the downloaded file to install it.

  3. If you are a homebrew fan, you can install it using this brew command: brew install python3

  4. To install homebrew package manager, see:

  5. Once you have homebrew installed, run brew install libsodium to install libsodium.


  1. Go to and download the latest libsodium package (libsodium-1.0.8-mingw.tar.gz is the latest version as of this writing)

  2. When you extract the contents of the downloaded tar file, you will see 2 folders with the names libsodium-win32 and libsodium-win64.

  3. As the name suggests, use the libsodium-win32 if you are using 32-bit machine or libsodium-win64 if you are using a 64-bit operating system.

  4. Copy the libsodium-x.dll from libsodium-win32\bin or libsodium-win64\bin to C:\Windows\System or System32 and rename it to libsodium.dll.

  5. Download the latest build ( is the latest build as of this writing) from here and run the downloaded executable.

Using a virtual environment (recommended)

We recommend creating a new Python virtual environment for trying out Plenum. a virtual environment is a Python environment which is isolated from the system's default Python environment (you can change that) and any other virtual environment you create. You can create a new virtual environment by:

virtualenv -p python3.5 <name of virtual environment>

And activate it by:

source <name of virtual environment>/bin/activate

Initializing Keep

init_plenum_raet_keep --name Alpha --seeds 000000000000000000000000000Alpha Alpha000000000000000000000000000 --force
init_plenum_raet_keep --name Beta --seeds 0000000000000000000000000000Beta Beta0000000000000000000000000000 --force
init_plenum_raet_keep --name Gamma --seeds 000000000000000000000000000Gamma Gamma000000000000000000000000000 --force
init_plenum_raet_keep --name Delta --seeds 000000000000000000000000000Delta Delta000000000000000000000000000 --force

Note: Seed can be any randomly chosen 32 byte value. It does not have to be in the format 00..<name of the node>.

Seeds used for generating clients

  1. Seed used for steward Bob's signing key pair 11111111111111111111111111111111
  2. Seed used for steward Bob's public private key pair 33333333333333333333333333333333
  3. Seed used for client Alice's signing key pair 22222222222222222222222222222222
  4. Seed used for client Alice's public private key pair 44444444444444444444444444444444

Running Node

start_plenum_node Alpha

Updating configuration

To update any configuration parameters, you need to update the in .plenum directory inside your home directory. eg. To update the node registry to use as host put these in your

from collections import OrderedDict

nodeReg = OrderedDict([
    ('Alpha', (('', 9701), '0490a246940fa636235c664b8e767f2a79e48899324c607d73241e11e558bbd7', 'ea95ae1c913b59b7470443d79a6578c1b0d6e1cad0471d10cee783dbf9fda655')),
    ('Beta', (('', 9703), 'b628de8ac1198031bd1dba3ab38077690ca9a65aa18aec615865578af309b3fb', '18833482f6625d9bc788310fe390d44dd268427003f9fd91534e7c382501cd3c')),
    ('Gamma', (('', 9705), '92d820f5eb394cfaa8d6e462f14708ddecbd4dbe0a388fbc7b5da1d85ce1c25a', 'b7e161743144814552e90dc3e1c11d37ee5a488f9b669de9b8617c4af69d566c')),
    ('Delta', (('', 9707), '3af81a541097e3e042cacbe8761c0f9e54326049e1ceda38017c95c432312f6f', '8b112025d525c47e9df81a6de2966e1b4ee1ac239766e769f19d831175a04264'))

cliNodeReg = OrderedDict([
    ('AlphaC', (('', 9702), '0490a246940fa636235c664b8e767f2a79e48899324c607d73241e11e558bbd7', 'ea95ae1c913b59b7470443d79a6578c1b0d6e1cad0471d10cee783dbf9fda655')),
    ('BetaC', (('', 9704), 'b628de8ac1198031bd1dba3ab38077690ca9a65aa18aec615865578af309b3fb', '18833482f6625d9bc788310fe390d44dd268427003f9fd91534e7c382501cd3c')),
    ('GammaC', (('', 9706), '92d820f5eb394cfaa8d6e462f14708ddecbd4dbe0a388fbc7b5da1d85ce1c25a', 'b7e161743144814552e90dc3e1c11d37ee5a488f9b669de9b8617c4af69d566c')),
    ('DeltaC', (('', 9708), '3af81a541097e3e042cacbe8761c0f9e54326049e1ceda38017c95c432312f6f', '8b112025d525c47e9df81a6de2966e1b4ee1ac239766e769f19d831175a04264'))