QCP: QuantizedCommunication Protocol // A Sub Token Semantic Protocol for Modular Language Model Systems

QCP (Quantized Communication Protocol) proposes a sub-token semantic communication standard for machine-to-machine interaction in modular language model systems. Instead of transmitting natural language messages between computational modules, QCP encodes semantic content into discrete integer codes using a shared vector-quantized codebook. The protocol defines encoding, transmission, decoding, confidence-aware escalation, and a dual-mode architecture with a formal fallback guarantee. The paper provides theoretical analysis (rate–distortion characterization, margin-based misrouting bound, structural cost comparison) and empirical validation across fifteen experiments covering fidelity, bandwidth compression, throughput, robustness, and deployment scenarios. Version 1.0 – Initial public preprint release.