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ETH 2.0(Serenity) Networking

Kevin Mai-Hsuan Chia

Ethereum Foundation

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About me

  • Kevin(Mai-Hsuan) Chia, 賈脈瑄
  • Ethereum Research, ETH 2.0 Python implementation
  • Github/gitter id: mhchia
  • mhchia@ethereum.org

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Peer-to-Peer networking in ETH 1.0

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ETH 1.0 Node

Dapp

Consensus

Peer-to-Peer networking

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ETH 1.0 Node

Dapp

Consensus

Peer-to-Peer networking

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Peer-to-Peer networking

Discovery

Gossiping

RPC calls between peers

  • broadcast_transaction
  • broadcast_block
  • Bootstrapping nodes
  • find_peer

​

  • GetBlockHeader
  • GetBlockBody

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ETH 2.0 Networking Requirement

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Requirement

  • Shard subscription: clients should be able to subscribe to one or more shards

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Requirement

​

  • Shard subscription: clients should be able to subscribe to one or more shards
    • And should only receive the data from the shards it has subscribed

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Requirement

​

  • Shard subscription: clients should be able to subscribe to one or more shards
    • And should only receive the data from the shards it has subscribed
  • Shard peer discovery

​

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  • broadcast_transaction
  • broadcast_block
  • broadcast_transaction_in_shard
  • broadcast_block_in_shard

Peer-to-Peer networking

Discovery

Gossiping

RPC calls between peers

  • Bootstrapping nodes
  • find_peer
  • find_peers_in_shard

​

  • GetBlockHeader
  • GetBlockBody
  • ...

ETH 2.0

networking

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Design

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Discovery: Discovery V5

  • Support topic advertisements
    • Nodes can advertise topics. Advertisements can be queried and nodes advertising a topic are found.
  • topic = “shard-{number}-(transaction|block)”

github.com/ethereum/devp2p/blob/master/discv5/discv5.md#node-discovery-protocol-v5

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RPC methods in Phase 0

​

github.com/ethereum/eth2.0-specs/pull/763

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RPC methods in Phase 0

  • Hello
  • Goodbye
  • Get Status
  • Request Beacon Block Roots
  • Beacon Block Headers
  • Beacon Block Bodies
  • Beacon Chain State

​

​

​

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Gossiping: PubSub

github.com/libp2p/go-libp2p-pubsub

publisher

subscriber

topic

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Gossiping: PubSub

  • topic = “shard-{number}-(transaction|block)”

​

publisher

subscriber

github.com/libp2p/go-libp2p-pubsub

topic

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libp2p

  • Is extracted from IPFS, and already used in many projects
  • Supports many networking modules

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Why libp2p?

  • Provides well-maintained modules we need
    • E.g. Kademlia DHT, GossipSub
  • Is supported in multple languages
    • Implemented in Go, Rust, Javascript, Nim, Python
    • libp2p-daemon usable for the non-implemented languages with bindings
  • Allows us to do experiments with various technology
    • E.g. QUIC, Tor

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devp2p v.s. libp2p

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Current status

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Testnets

  • Several clients launched client-internal testnets for phase 0
  • Some clients use libp2p, while some others don’t, implementing with a minimal wire protocol called Hobbits(https://github.com/Whiteblock/hobbits)

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20190409 ETH2.0 Networking workshop

https://notes.ethereum.org/Zk4oL1m_SV2jQR8poRQrPg#Propagation

  • Networking spec
  • libp2p daemon
  • libp2p pubsub

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Ongoing R&D works

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