Lightspeed Notification Protocol

This document defines the Lightspeed Notification Protocol (LSN), a hardware-accelerated signaling mechanism designed for sub-100 microsecond network convergence in AI/ML data center fabrics. By operating entirely within the forwarding plane, LSN bypasses traditional CPU-based latencies to propagate link failures and congestion via a hardware-efficient encoding. It serves as a high- speed complement to routing protocols like BGP, providing an immediate hardware "veto" to prune congested/failed paths while maintaining control-plane stability for path recovery.