Node Configuration

Fed-BioMed framework has 2 main components: node and researcher. A node stores private datasets and performs training in response to researcher's train requests. It communicates directly with the researcher component using RPC protocol.

A basic node component configuration contains the following settings:

• a python environment
• a unique node id
• security parameters such as training plan approval mode, hashing algorithms
• connection credentials for the researcher component

Environment for Nodes

A node requires a conda environment to be able to run. This environment provides the necessary python modules for both the task management part and the model training part. Thanks to Fed-BioMed's Node CLI, this conda environment can be created easily.

$ ${FEDBIOMED_DIR}/scripts/configure_conda node

The command above creates the fedbiomed-node conda environment. You can find more details in installation tutorial.

Note: FEDBIOMED_DIR represents the path of the base Fed-BioMed project directory.

Configuration Files

A configuration file is an ini file that is located in the ${FEDBIOMED_DIR}/etc directory. Each configuration file is unique to one node.

The configuration file is structured following the sections below:

• Default Parameters:

  • id: This is the unique ID that identifies the node.
  • component: Specifies the component type. It is always NODE for node component
  • version: Version of the configuration format to avoid using older configuration files with recent Fed-BioMed versions.
  • db: Relative path to the node's database, from this configuration file

• MPSDPZ (Secure Aggregation)

  • MP-SDPZ is the library used for secure aggregation to be able to generate private/public keys securely. Please see the details Here.
  • private_key: Path to private key to use in secure HTTP connection.
  • public_key: Path to public key to share with other parties (nodes and researcher) use in secure HTTP connection.
  • mpspdz_ip: The IP address that will be used for launching MP-SPDZ instance.
  • mpsdpz_port: The port that will be used for launching MP-SPDZ instance.
  • allow_default_biprimes: Boolean (True/False) to allow default biprimes for key generation.
  • default_biprimes_dir ": Relative path to the directory where default biprimes files are kept, from this configuration file

• Researcher:

  • ip: The IP address of the researcher component that the node will connect to.
  • port: The port of the researcher component.

• Security Parameters:

  • hashing_algorithm: The algorithm will be used for hashing training plan scripts to verify if the requested training plan matches the one approved on the node side.
  • training_plan_approval: Boolean value to switch training plan approval to verify training plan scripts before the training.
  • allow_default_training_plans: Boolean value to enable automatic approval of example training plans provided by Fed-BioMed.
  • secure_aggregation: Boolean parameter (True/False) to activate secure aggregation.
  • force_secure_aggregation: Boolean parameter (True/False) to force secure aggregation for every action that uses local dataset.

An example for a config file is shown below;

[default]
id = node_73768d5f-6a66-47de-8533-1291c4ef59d1
component = NODE
version = 2
db = ../var/db_NODE_94572b0f-f55c-4167-b729-f16247c35a04.json

[mpspdz]
private_key = certs/cert_node_73768d5f-6a66-47de-8533-1291c4ef59d1/MPSPDZ_certificate.key
public_key = certs/cert_node_73768d5f-6a66-47de-8533-1291c4ef59d1/MPSPDZ_certificate.pem
mpspdz_ip = localhost
mpspdz_port = 14004
allow_default_biprimes = True
default_biprimes_dir = ../envs/common/default_biprimes

[security]
hashing_algorithm = SHA256
allow_default_training_plans = True
training_plan_approval = False
secure_aggregation = True
force_secure_aggregation = False

[researcher]
ip = localhost
port = 50051

Starting Nodes with Config Files

Starting nodes with specific config creates a new configuration file. The following command creates a specific config file with default settings and starts the node.

$ ./scripts/fedbiomed_run node --config config-n1.ini start

If you run this command, you can see a new config file created in the etc/ directory of the Fed-BioMed. Each node that runs in the same host should have a different node id and configuration file. Starting another node that uses the same config file does not raise an error message but results in errors during training. Therefore, if you launch multiple nodes please make sure to use different configurations.

The --config flag can be used with any of the node subcommands as in the examples below.

$ ./scripts/fedbiomed_run node --config config-n1.ini dataset list
$ ./scripts/fedbiomed_run node --config config-n1.ini dataset add

Creating advanced configuration files for node components

The command below can be used to create, or optionally recreate (-f), a configuration file for a node with CONFIGURATION_FILE_NAME name.

${FEDBIOMED_DIR}/scripts/fedbiomed_run configuration create -c NODE -n [CONFIGURATION_FILE_NAME]

You may view and edit your new configuration file at the location ${FEDBIOMED_DIR}/etc/[CONFIGURATION_FILE_NAME].

Environment variables can be used to parametrize the various options for creating a configuration file. The fields that can be controlled, their associated environment variable, and default value are described below:

[security]:
- allow_default_training_plans: ALLOW_DEFAULT_TRAINING_PLANS, True
- training_plan_approval: ENABLE_TRAINING_PLAN_APPROVAL, False
- secure_aggregation: SECURE_AGGREGATION, True
- force_secure_aggregation: FORCE_SECURE_AGGREGATION, False

[researcher]:
- ip: RESEARCHER_SERVER_HOST, ${IP_ADDRESS}, if not set: localhost
- port: RESEARCHER_SERVER_PORT, 50051

You may also explore them through the command's help menu

${FEDBIOMED_DIR}/scripts/fedbiomed_run configuration create -h

Examples

Create the new configuration file ${FEDBIOMED_DIR}/etc/node_1.ini with a specified IP and port for the researcher, and disabling secure aggregation. Forcefully delete and recreate the file if it was already existing.

$ RESEARCHER_SERVER_HOST=121.203.21.147 RESEARCHER_SERVER_PORT=8909 SECURE_AGGREGATION=0 ${FEDBIOMED_DIR}/scripts/fedbiomed_run configuration create -c NODE -n node_1.ini -f