Developer Resources
Block ExplorerGitHubRun a NodeMigration GuideETN Testnet Faucet
  • Overview
  • Foundational topics
    • Intro to the Electroneum Smart Chain
    • Intro to ETN
    • Intro to dapps
    • Web2 vs Web3
    • Accounts
    • Transactions
    • Blocks
    • Electroneum Virtual Machine (EVM)
      • Opcodes
    • Gas and Fees
    • Nodes and clients
    • Networks
    • Consensus mechanisms
      • IBFT
  • Electroneum Stack
    • Intro to the stack
    • Smart contracts
    • Development networks
    • Development frameworks
    • Electroneum client APIs
      • JavaScript APIs
      • JSON-RPC
    • Storage
    • Integrated Development Environments (IDEs)
    • Metamask
  • Advanced
    • Bridges
    • Standards
      • Token standards
        • ERC-20 Fungible Tokens
        • ERC-721 NFTs
    • Oracles
    • Networking layer
      • Network addresses
    • Data structures and encoding
      • Patricia Merkle Trie
      • Recursive-length prefix (RLP)
      • Web3 secret storage definition
  • Design fundamentals
    • Intro to design and UX
  • ETN-SC Client
    • Getting started
      • Introduction
      • Hardware requirements
      • Instaling ETN-SC
    • Fundamentals
      • Command-line options
      • Security
      • Sync-modes
      • Account management
      • Databases
      • Backup & restore
      • Logs
      • Connecting to peers
      • Pruning
      • Private networks
      • Config files
      • Light client
    • Interacting with ETN-SC
      • JSON-RPC Server
        • Batch requests
        • Real-time events
      • JSON-RPC Namespaces
        • admin
        • clique
        • debug
        • eth
        • istanbul
        • les
        • miner
        • net
        • personal
        • txpool
      • JS Console
      • JS Console 2: Contracts
      • GraphQL Server
    • Developers
      • Introduction
      • Dapp developers
        • Dev mode
        • Go API
        • Go Account Management
        • Go Contract Bindings
      • EVM tracing
        • Introduction
        • Basic traces
        • Built-in tracers
        • Custom EVM tracer
        • Tutorial for JavaScript tracing
      • ETN-SC developer
        • Developer guide
        • Disclosures
        • DNS discovery setup guide
        • Code review guidelines
      • Contributing
    • Monitoring
      • Creating Dashboards
      • Understanding Dashboards
      • Ethstats
      • Metrics
    • Tools
      • Clef
        • Introduction
        • APIs
        • Rules
        • Setup
        • Datatypes
        • Tutorial
        • Clique-signing
      • abigen
      • devp2p
    • FAQs
  • Migration to Smart Chain
    • Overview
    • How to Migrate
      • ETN Online Wallets
      • Paper Wallets
      • CLI Wallet Users
      • Exchange Holders
      • Exchanges
    • Bridge Smart Contract
  • Misc. Guides
    • Set up Ledger + Metamask
  • MY.ELECTRONEUM.COM
    • Vendor API
Powered by GitBook
On this page
  • ENR Decoding
  • Node Key Management
  • Maintaining DNS Discovery Node Lists
  • Node Set Utilities
  • Discovery v4 Utilities
  • Discovery v5 Utilities
  • Discovery Test Suites
  • Eth Protocol Test Suite
  • Eth66 Test Suite
  • Summary

Was this helpful?

  1. ETN-SC Client
  2. Tools

devp2p

PreviousabigenNextFAQs

Last updated 1 year ago

Was this helpful?

is a set of network protocols that form the Electroneum peer-to-peer network. The DevP2P specifications define precisely how nodes should find each other and communicate. Etn-sc implements the DevP2P specifications in Go.

The DevP2P stack includes the low-level peer-to-peer protocols that define discovery and secure sessions between nodes such as:

  • : A standard format for connectivity information for a node

  • : Defines how nodes find each other.

  • : Defines a TCP based transport system for communication between nodes.

DevP2P also includes the RLPx-based application level protocols including:

  • : facilitates exchange of blockchain data between peers

  • : enables exchange of snapshots between peers

  • : protocol used by light clients

To debug and develop these networking components, Etn-sc includes a command line tool called devp2p.

This page will outline some of devp2ps built-in tools.

ENR Decoding

Electroneum Node Records can be decoded, verified and displayed to the terminal using enrdump. It takes the ENR in its encoded form, which is the base64 encoding of its RLP representation. A decoded human-readable text representation is displayed.

Use devp2p enrdump <base64> to verify and display an Electroneum Node Record.

The following is an example of the data returned by enrdump:

./devp2p enrdump "enr:-J24QG3pjTFObcDvTOTJr2qPOTDH3-YxDqS47Ylm-kgM5BUwb1oD5Id6fSRTfUzTahTa7y4TWx_HSV7wri7T6iYtyAQHg2V0aMfGhLjGKZ2AgmlkgnY0gmlwhJ1a19CJc2VjcDI1NmsxoQPlCNb7N__vcnsNC8YYkFkmNj8mibnR5NuvSowcRZsLU4RzbmFwwIN0Y3CCdl-DdWRwgnZf" Node ID: 001816492db22f7572e9eea1c871a2ffe75c28162a9fbc5a9d240e480a7c176f URLv4: ./devp2p enrdump  "enr:-J24QG3pjTFObcDvTOTJr2qPOTDH3-YxDqS47Ylm-kgM5BUwb1oD5Id6fSRTfUzTahTa7y4TWx_HSV7wri7T6iYtyAQHg2V0aMfGhLjGKZ2AgmlkgnY0gmlwhJ1a19CJc2VjcDI1NmsxoQPlCNb7N__vcnsNC8YYkFkmNj8mibnR5NuvSowcRZsLU4RzbmFwwIN0Y3CCdl-DdWRwgnZf"
Node ID: 001816492db22f7572e9eea1c871a2ffe75c28162a9fbc5a9d240e480a7c176f
URLv4:   enode://e508d6fb37ffef727b0d0bc618905926363f2689b9d1e4dbaf4a8c1c459b0b534dcdf84342b78250a6dc013c9ee9f89d095d7a6d1ef0c5f4c57a083b22c557ef@157.90.215.208:30303
Record has sequence number 7 and 7 key/value pairs.
  "eth"       c7c684b8c6299d80
  "id"        "v4"
  "ip"        157.90.215.208
  "secp256k1" a103e508d6fb37ffef727b0d0bc618905926363f2689b9d1e4dbaf4a8c1c459b0b53
  "snap"      c0
  "tcp"       30303
  "udp"       30303

Node Key Management

The devp2p key ... command family deals with node key files.

Run devp2p key generate mynode.key to create a new node key in the mynode.key file.

Run devp2p key to-enode mynode.key -ip 127.0.0.1 -tcp 30303 to create an enode:// URL corresponding to the given node key and address information.

Maintaining DNS Discovery Node Lists

The devp2p command can create and publish DNS discovery node lists.

Run devp2p dns sign <directory> to update the signature of a DNS discovery tree.

Run devp2p dns sync <enrtree-URL> to download a complete DNS discovery tree.

Run devp2p dns to-cloudflare <directory> to publish a tree to CloudFlare DNS.

Run devp2p dns to-route53 <directory> to publish a tree to Amazon Route53.

Node Set Utilities

There are several commands for working with JSON node set files. These files are generated by the discovery crawlers and DNS client commands. Node sets also used as the input of the DNS deployer commands.

Run devp2p nodeset info <nodes.json> to display statistics of a node set.

Run devp2p nodeset filter <nodes.json> <filter flags...> to write a new, filtered node set to standard output. The following filters are supported:

  • -limit <N> limits the output set to N entries, taking the top N nodes by score

  • -ip <CIDR> filters nodes by IP subnet

  • -min-age <duration> filters nodes by 'first seen' time

  • -eth-network <mainnet/testnet> filters nodes by "etn" ENR entry

  • -les-server filters nodes by LES server support

  • -snap filters nodes by snap protocol support

For example, given a node set in nodes.json, you could create a filtered set containing up to 20 eth mainnet nodes which also support snap sync using this command:

devp2p nodeset filter nodes.json -eth-network mainnet -snap -limit 20

Discovery v4 Utilities

Run devp2p discv4 ping <enode/ENR> to ping a node.

Run devp2p discv4 resolve <enode/ENR> to find the most recent node record of a node in the DHT.

Run devp2p discv4 crawl <nodes.json path> to create or update a JSON node set.

Discovery v5 Utilities

Run devp2p discv5 ping <ENR> to ping a node.

Run devp2p discv5 resolve <ENR> to find the most recent node record of a node in the discv5 DHT.

Run devp2p discv5 listen to run a Discovery v5 node.

Run devp2p discv5 crawl <nodes.json path> to create or update a JSON node set containing discv5 nodes.

Discovery Test Suites

The devp2p command also contains interactive test suites for Discovery v4 and Discovery v5. To run these tests a networking environment must be set up with two separate UDP listening addresses are available on the same machine. The two listening addresses must also be routed such that they are able to reach the node you want to test.

For example, to run the test on the local host when the node under test is also on the local host, assign two IP addresses (or a larger range) to the loopback interface. On macOS, this can be done by executing the following command:

sudo ifconfig lo0 add 127.0.0.2

Either test suite can then be run as follows:

  1. Start the node under test first, ensuring that it won't talk to the Internet (i.e. disable bootstrapping). An easy way to prevent unintended connections to the global DHT is listening on 127.0.0.1.

  2. Get the ENR of the node and store it in the NODE environment variable.

  3. Start the test by running devp2p discv5 test -listen1 127.0.0.1 -listen2 127.0.0.2 $NODE.

Eth Protocol Test Suite

To run the eth protocol test suite, the node needs to be initialized as follows:

  1. initialize the Etn-sc node with the genesis.json file contained in the testdata directory

  2. import the halfchain.rlp file in the testdata directory

  3. run Etn-sc with the following flags:

etn-sc --datadir <datadir> --nodiscover --nat=none --networkid 51420 --verbosity 5

Then, run the following command, replacing <enode> with the enode of the Etn-sc node:

devp2p rlpx eth-test <enode> cmd/devp2p/internal/ethtest/testdata/chain.rlp cmd/devp2p/internal/ethtest/testdata/genesis.json

Repeat the above process (re-initialising the node) in order to run the Eth Protocol test suite again.

Eth66 Test Suite

The Eth66 test suite is also a conformance test suite for the eth 66 protocol version specifically. To run the eth66 protocol test suite, initialize a Etn-sc node as described above and run the following command, replacing <enode> with the enode of the Etn-sc node:

devp2p rlpx eth66-test <enode> cmd/devp2p/internal/ethtest/testdata/chain.rlp cmd/devp2p/internal/ethtest/testdata/genesis.json

Summary

This page introduced the DevP2P stack that defines Electroneum's peer-to-peer network and the devp2p command line tool that comes bundled with Etn-sc. The devp2p tools enables Etn-sc developers to work on the peer-to-peer network.

Read more on or browse the .

More information about these commands can be found in the .

The devp2p discv4 ... command family deals with the protocol.

The devp2p discv5 ... command family deals with the protocol. This protocol is currently under active development.

The Eth Protocol test suite is a conformance test suite for the .

DevP2P
Ethereum Node Records
Discovery protocol
RLPx protocol
Ethereum Wire Protocol
Ethereum Snapshot Protocol
Light Ethereum Subprotocol
DNS Discovery Setup Guide
Node Discovery v4
Node Discovery v5
eth protocol
specs
Electroneum Node Records