Session-Bound Zero-Knowledge Authorization for SRv6 Programmable Data Planes

Abstract

The integration of continuous Zero Trust Architecture (ZTA) into Segment Routing over IPv6 (SRv6) networks introduces severe performance bottlenecks and physical constraints of the Maximum Transmission Unit (MTU). Specifically, naively embedding massive Zero-Knowledge Proof (ZKP) for per-packet authentication inevitably triggers catastrophic fragmentation and disrupts stateless forwarding. To address these fundamental limitations, this paper proposes a novel session-bound zero-knowledge authorization framework tailored for SRv6 programmable data planes. Our architecture explicitly decouples heavyweight cryptographic validations from the active forwarding path. Massive ZKP payloads are processed asynchronously via payload transmission in the control plane, while the data plane enforces line-rate access control using lightweight 32-byte capability tokens encapsulated in customized SRv6 extension headers. Furthermore, to mathematically balance robust security with forwarding efficiency, we formulate the dynamic verification process as a risk-aware Partially Observable Markov Decision Process (POMDP). Using in-band network telemetry, we derive an Adaptive Threshold Verification (ATV) algorithm that yields a closed-form <inline-formula> <tex-math notation="LaTeX">$O(1)$ </tex-math></inline-formula> complexity optimal scheduling policy. Extensive evaluations demonstrate that the decoupled mechanism seamlessly resolves the MTU bottleneck, maintaining stable baseline throughput under massive concurrent sessions. Concurrently, the ATV algorithm intelligently adapts to real-time threat intensities, conserving control-plane resources during safe periods while instantaneously triggering precise re-verifications against covert and volumetric cyberattacks.