ProSecutor: Protecting Mobile AIGC Services on Two-Layer Blockchain via Reputation and Contract Theoretic Approaches

TL;DR

ProSecutor addresses the risk of unprotected MASP interactions in mobile AIGC by building a two-layer blockchain that records tamper-proof reputation and supports atomic fee-ownership transfers. It introduces OS^2A to fuse objective QoE KPIs with subjective reputation signals, and leverages contract theory with diffusion-DRL to design incentive-compatible payment schemes. The architecture uses reputation roll-ups on Layer-2 and duplex hash-locked payment channels to achieve high throughput and low storage overhead, validated by a BlockEmulator prototype showing 12.5x throughput gains and 67.5% storage savings. Empirical results confirm MASP selection quality, contract designs, and secure, atomic transfers, with comprehensive security analysis and demonstrations of defense against typical attacks in mobile networks.

Abstract

Mobile AI-Generated Content (AIGC) has achieved great attention in unleashing the power of generative AI and scaling the AIGC services. By employing numerous Mobile AIGC Service Providers (MASPs), ubiquitous and low-latency AIGC services for clients can be realized. Nonetheless, the interactions between clients and MASPs in public mobile networks, pertaining to three key mechanisms, namely MASP selection, payment scheme, and fee-ownership transfer, are unprotected. In this paper, we design the above mechanisms using a systematic approach and present the first blockchain to protect mobile AIGC, called ProSecutor. Specifically, by roll-up and layer-2 channels, ProSecutor forms a two-layer architecture, realizing tamper-proof data recording and atomic fee-ownership transfer with high resource efficiency. Then, we present the Objective-Subjective Service Assessment (OS^{2}A) framework, which effectively evaluates the AIGC services by fusing the objective service quality with the reputation-based subjective experience of the service outcome (i.e., AIGC outputs). Deploying OS^{2}A on ProSecutor, firstly, the MASP selection can be realized by sorting the reputation. Afterward, the contract theory is adopted to optimize the payment scheme and help clients avoid moral hazards in mobile networks. We implement the prototype of ProSecutor on BlockEmulator.Extensive experiments demonstrate that ProSecutor achieves 12.5x throughput and saves 67.5\% storage resources compared with BlockEmulator. Moreover, the effectiveness and efficiency of the proposed mechanisms are validated.

Figures (10)

• Figure 1: The structure of this paper and the system model of the mobile AIGC market.
• Figure 2: The data structure of ProSecutor. $L$ denotes the RT leaves containing MASP's address and its reputation.
• Figure 3: Illustration of atomic fee-ownership transfers. The operations framed by red dotted lines construct one atomic operation that should be executed simultaneously.
• Figure 4: A series of AIGC images. Image (a) and the others are generated by Stable Diffusion 2.1 and Craiyon V3, respectively. The other configurations are default.
• Figure 5: The illustration of transaction pool and the fitting of Ethereum transaction fee.