Whisper Wire Protocol

Contents

• Whisper Sub-protocol
• Session Management

Peer-to-peer communications between nodes running Whisper clients run using the underlying ÐΞVp2p Wire Protocol.

This is a preliminary wire protocol for the Whisper subsystem. It will change.

Whisper Sub-protocol

Status [+0x00: P, protocolVersion: P] Inform a peer of the whisper status. This message should be send after the initial handshake and prior to any whisper related messages.

• protocolVersion is one of:
  • 0x02 for PoC-7.

Messages [+0x01: P, [expiry1: P, ttl1: P, [topic1x1: B_4, topic1x2: B_4, ...], data1: B, nonce1: P], [expiry2: P, ...], ...] Specify one or more messages. Nodes should not resend the same message to a peer in the same session, nor send a message back to a peer from which it received. This packet may be empty. The packet must be sent at least once per second, and only after receiving a Messages message from the peer.

Session Management

For the Whisper sub-protocol, upon an active session, a Status message must be sent. Following the reception of the peer's Status message, the Whisper session is active. The peer with the greatest Node Id should send a Messages message to begin the message rally. From that point, peers take it in turns to send (possibly empty) Messages packets.