Crate reth_discv4

Discovery v4 implementation: https://github.com/ethereum/devp2p/blob/master/discv4.md

Discv4 employs a kademlia-like routing table to store and manage discovered peers and topics. The protocol allows for external IP discovery in NAT environments through regular PING/PONG’s with discovered nodes. Nodes return the external IP address that they have received and a simple majority is chosen as our external IP address. If an external IP address is updated, this is produced as an event to notify the swarm (if one is used for this behaviour).

This implementation consists of a Discv4 and Discv4Service pair. The service manages the state and drives the UDP socket. The (optional) Discv4 serves as the frontend to interact with the service via a channel. Whenever the underlying table changes service produces a DiscoveryUpdate that listeners will receive.

Feature Flags

• serde (default): Enable serde support
• test-utils: Export utilities for testing

Modules

• error
  Error types that can occur in this crate.
• proto
  Discovery v4 protocol implementation.
• test_utilstest-utils
  Mock discovery support

Structs

• Discv4
  The Discv4 frontend
• Discv4Config
  Configuration parameters that define the performance of the discovery network.
• Discv4ConfigBuilder
  Builder type for Discv4Config
• Discv4Service
  Manages discv4 peer discovery over UDP.
• NodeRecord
  Represents a ENR in discovery.

Enums

• DiscoveryUpdate
  Represents node related updates state changes in the underlying node table
• Discv4Event
  The Event type the Service stream produces.
• NatResolver
  reexport to get public ip. All builtin resolvers.

Constants

• DEFAULT_DISCOVERY_ADDR
  The default address for discv4 via UDP
• DEFAULT_DISCOVERY_ADDRESS
  The default address for discv4 via UDP: “0.0.0.0:30303”
• DEFAULT_DISCOVERY_PORT
  The default port for discv4 via UDP

Functions

• external_ip
  reexport to get public ip. Attempts to produce an IP address with all builtin resolvers (best effort).