Cached Model-as-a-Resource: Provisioning Large Language Model Agents for Edge Intelligence in Space-air-ground Integrated Networks
Minrui Xu, Dusit Niyato, Hongliang Zhang, Jiawen Kang, Zehui Xiong, Shiwen Mao, Zhu Han
TL;DR
This work tackles provisioning LLM agent services across space-air-ground integrated networks by treating cached LLM models as a resource and introducing an AoT-based, least AoT caching strategy to manage context-window efficiency at edge servers. It pairs this with a DRL-guided, strategy-proof market mechanism (DQMSB) that uses a price-scaling factor to maximize total surplus while avoiding adverse selection. The approach yields substantial gains in efficiency (notably around 23% higher surplus over baselines) and guarantees anonymity, strategy-proofness, and adverse-selection-freeness. The combination of AoT-aware caching and DRL-based auction design offers a practical framework for scalable, low-latency edge intelligence in SAGINs with satellites relaying requests to cloud datacenters.
Abstract
Edge intelligence in space-air-ground integrated networks (SAGINs) can enable worldwide network coverage beyond geographical limitations for users to access ubiquitous and low-latency intelligence services. Facing global coverage and complex environments in SAGINs, edge intelligence can provision approximate large language models (LLMs) agents for users via edge servers at ground base stations (BSs) or cloud data centers relayed by satellites. As LLMs with billions of parameters are pre-trained on vast datasets, LLM agents have few-shot learning capabilities, e.g., chain-of-thought (CoT) prompting for complex tasks, which raises a new trade-off between resource consumption and performance in SAGINs. In this paper, we propose a joint caching and inference framework for edge intelligence to provision sustainable and ubiquitous LLM agents in SAGINs. We introduce "cached model-as-a-resource" for offering LLMs with limited context windows and propose a novel optimization framework, i.e., joint model caching and inference, to utilize cached model resources for provisioning LLM agent services along with communication, computing, and storage resources. We design "age of thought" (AoT) considering the CoT prompting of LLMs, and propose a least AoT cached model replacement algorithm for optimizing the provisioning cost. We propose a deep Q-network-based modified second-bid (DQMSB) auction to incentivize network operators, which can enhance allocation efficiency by 23% while guaranteeing strategy-proofness and free from adverse selection.
