EIP-8178

Binary SSZ Transport for the Engine API

Specifies a binary SSZ transport as an alternative to JSON-RPC for Engine API communication

Status history

Draft1 Mar 2026

Abstract

This EIP specifies a binary SSZ transport for Engine API communication between consensus layer (CL) and execution layer (EL) clients. The binary transport replaces JSON-RPC with resource-oriented REST endpoints and raw SSZ encoding for fast, efficient CL-EL communication. SSZ container definitions are provided for all Engine API structures and methods across all forks for backwards compatibility.

Created: 1 Mar 2026
Authors: Giulio Rebuffo
Upgrades: Not listed in any upgrade
Requires: —
Required by: —

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