Convergence of Byzantine-Resilient Gradient Tracking via Probabilistic Edge Dropout
- URL: http://arxiv.org/abs/2604.00449v2
- Date: Sat, 04 Apr 2026 05:44:27 GMT
- Title: Convergence of Byzantine-Resilient Gradient Tracking via Probabilistic Edge Dropout
- Abstract summary: We study distributed optimization over networks with Byzantine agents that may send arbitrary adversarial messages.<n>We propose emphGradient Tracking with Probabilistic Edge Dropout and Leaky Integration (GT-PD-L)<n>GT-PD-L outperforms coordinate-wise mean by up to 4.3 percentage points under stealth attacks.
- Score: 1.3902537392439644
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We study distributed optimization over networks with Byzantine agents that may send arbitrary adversarial messages. We propose \emph{Gradient Tracking with Probabilistic Edge Dropout} (GT-PD), a stochastic gradient tracking method that preserves the convergence properties of gradient tracking under adversarial communication. GT-PD combines two complementary defense layers: a universal self-centered projection that clips each incoming message to a ball of radius $τ$ around the receiving agent, and a fully decentralized probabilistic dropout rule driven by a dual-metric trust score in the decision and tracking channels. This design bounds adversarial perturbations while preserving the doubly stochastic mixing structure, a property often lost under robust aggregation in decentralized settings. Under complete Byzantine isolation ($p_b=0$), GT-PD converges linearly to a neighborhood determined solely by stochastic gradient variance. For partial isolation ($p_b>0$), we introduce \emph{Gradient Tracking with Probabilistic Edge Dropout and Leaky Integration} (GT-PD-L), which uses a leaky integrator to control the accumulation of tracking errors caused by persistent perturbations and achieves linear convergence to a bounded neighborhood determined by the stochastic variance and the clipping-to-leak ratio. We further show that under two-tier dropout with $p_h=1$, isolating Byzantine agents introduces no additional variance into the honest consensus dynamics. Experiments on MNIST under Sign Flip, ALIE, and Inner Product Manipulation attacks show that GT-PD-L outperforms coordinate-wise trimmed mean by up to 4.3 percentage points under stealth attacks.
Related papers
- One Step, One Lead: Mitigating Higher-Order Interference in Multi-Domain Reinforcement Learning via Cross-Step Control [62.82372407840088]
We show that same-point domain gradients may remain nearly even when consecutive realized updates partially reverse one another in output space.<n>We propose OSOL, which designates a focus domain at each iteration, to rank token-level rebound risk.<n>OSOL reaches a domain-macro average of 0.4822, improving by 5.7% over the strongest compared baseline, without explicit higher-order differentiation.
arXiv Detail & Related papers (2026-09-06T08:32:59Z) - Scale-Consistent Posterior Dynamics for Diffusion Inverse Problems [16.685352002333225]
Posterior sampling with a pretrained diffusion prior is governed by a conditional score whose likelihood component is generally intractable.<n>We show that a noise-conditioned path whose targets approach the clean posterior produces a continuous surrogate SDE.<n>Experiments on FFHQ and ImageNet with 100 score evaluations demonstrate competitive reconstruction fidelity for superresolution and deblurring.
arXiv Detail & Related papers (2026-08-15T09:38:41Z) - Scalable Policy Optimization for Networked Multi-Agent Reinforcement Learning with Continuous State-Action Spaces [16.43184149906767]
We develop an algorithm for cooperative reinforcement learning in networked decision processes with continuous state and action spaces.<n>Each agent maintains a local actor over a graph neighborhood, and a localized temporal-difference critic evaluates a truncated actionvalue function.
arXiv Detail & Related papers (2026-07-20T22:41:43Z) - Stability Annealing Selects the Implicit Bias of Smoothed Sign Descent: A Rate-Indexed Barrier Path on Separable Data [3.7437735326653883]
This paper studies the rate-controlled middle case for full-batch linear classification on separable data.<n>For memoryless stability-annealed smoothed-sign descent with weighted exponential loss, we prove that the normalized iterates converge to the minimizer of a convex Burg-type barrier over a margin slice.
arXiv Detail & Related papers (2026-07-07T08:55:35Z) - A Step Towards Robust Unsupervised Domain Adaptation via Fine-Tuning and Reinforcement Learning [2.436631469537453]
We propose textbfSFT+RL, a two-stage robust UDA framework that integratesSupervised Fine Tuning and Reinforcement Learning.<n>textbfSFT+RL achieves average improvements of textbf10.2% in clean accuracy and textbf15.8% in adversarial robustness across three datasets.
arXiv Detail & Related papers (2026-07-03T20:56:12Z) - Byzantine-Robust and Differentially Private Federated Optimization under Weaker Assumptions [89.52532304099522]
Federated Learning (FL) enables clients to collaboratively train a shared model without centralizing their raw data, offering an inherent level of privacy.<n> gradients and model updates can still leak sensitive information, while malicious servers may mount adversarial attacks such as Byzantine manipulation.<n>These vulnerabilities highlight the need to address differential privacy (DP) and Byzantine robustness within a unified framework.<n>We propose Byz-Clip21-SGD2M, a new algorithm that integrates robust aggregation with double momentum and carefully designed clipping.
arXiv Detail & Related papers (2026-03-24T17:39:09Z) - Beyond Reward Suppression: Reshaping Steganographic Communication Protocols in MARL via Dynamic Representational Circuit Breaking [0.0]
steganographic collusion, where agents develop private protocols to evade monitoring, presents a critical AI safety threat.<n>Existing defenses, limited to behavioral or reward layers, fail to detect coordination in latent communication channels.<n>We introduce the Dynamic Representational Circuit Breaker (DRCB), an architectural defense operating at the optimization substrate.
arXiv Detail & Related papers (2026-03-07T04:14:38Z) - SENTINEL: Stagewise Integrity Verification for Pipeline Parallel Decentralized Training [54.8494905524997]
Decentralized training introduces critical security risks when executed across untrusted, geographically distributed nodes.<n>We propose SENTINEL, a verification mechanism for pipeline parallelism (PP) training without duplication.<n>Experiments demonstrate successful training of up to 4B- parameter LLMs across untrusted distributed environments with up to 176 workers while maintaining model convergence and performance.
arXiv Detail & Related papers (2026-03-03T23:51:10Z) - Stability and Generalization of Push-Sum Based Decentralized Optimization over Directed Graphs [55.77845440440496]
Push-based decentralized communication enables optimization over communication networks, where information exchange may be asymmetric.<n>We develop a unified uniform-stability framework for the Gradient Push (SGP) algorithm.<n>A key technical ingredient is an imbalance-aware generalization bound through two quantities.
arXiv Detail & Related papers (2026-02-24T05:32:03Z) - BadCLIP++: Stealthy and Persistent Backdoors in Multimodal Contrastive Learning [73.46118996284888]
Research on backdoor attacks against multimodal contrastive learning models faces two key challenges: stealthiness and persistence.<n>We propose BadCLIP++, a unified framework that tackles both challenges.<n>For stealthiness, we introduce a semantic-fusion QR micro-trigger that embeds imperceptible patterns near task-relevant regions.<n>For persistence, we stabilize trigger embeddings via radius shrinkage and centroid alignment.
arXiv Detail & Related papers (2026-02-19T08:31:16Z) - Silent Inconsistency in Data-Parallel Full Fine-Tuning: Diagnosing Worker-Level Optimization Misalignment [27.352639822596146]
Cross-worker divergence in losses and gradients can remain invisible under conventional monitoring signals.<n>We propose a model-agnostic diagnostic framework that quantifies worker-level consistency using training signals readily available in standard pipelines.
arXiv Detail & Related papers (2026-02-16T04:42:30Z) - Generalizing GNNs with Tokenized Mixture of Experts [75.8310720413187]
We show that improving stability requires reducing reliance on shift-sensitive features, leaving an irreducible worst-case generalization floor.<n>We propose STEM-GNN, a pretrain-then-finetune framework with a mixture-of-experts encoder for diverse computation paths.<n>Across nine node, link, and graph benchmarks, STEM-GNN achieves a stronger three-way balance, improving robustness to degree/homophily shifts and to feature/edge corruptions while remaining competitive on clean graphs.
arXiv Detail & Related papers (2026-02-09T22:48:30Z) - Spectral Sentinel: Scalable Byzantine-Robust Decentralized Federated Learning via Sketched Random Matrix Theory on Blockchain [0.0]
Byzantine clients poison gradients under heterogeneous (Non-IID) data.<n>We propose Spectral Sentinel, a Byzantine detection and aggregation framework.<n>We implement the full system with blockchain integration on Polygon networks.
arXiv Detail & Related papers (2025-12-14T09:43:03Z) - DPAC: Distribution-Preserving Adversarial Control for Diffusion Sampling [0.7866885337535715]
Adversarially guided diffusion sampling often achieves the target class, but sample quality degrades as deviations between the adversarially controlled and nominal trajectories accumulate.<n>We formalize this degradation as a path-space Kullback-Leibler divergence(path-KL) between controlled and nominal (uncontrolled) diffusion processes.<n>We show that minimizing this path-KL simultaneously tightens upper bounds on both the Wasserstein distance and Fréchet Inception Distance (FID), revealing a connection between adversarial control energy and perceptual fidelity.
arXiv Detail & Related papers (2025-12-01T00:15:05Z) - Unsupervised Conformal Inference: Bootstrapping and Alignment to Control LLM Uncertainty [49.19257648205146]
We propose an unsupervised conformal inference framework for generation.<n>Our gates achieve close-to-nominal coverage and provide tighter, more stable thresholds than split UCP.<n>The result is a label-free, API-compatible gate for test-time filtering.
arXiv Detail & Related papers (2025-09-26T23:40:47Z) - On the Practicality of Differential Privacy in Federated Learning by
Tuning Iteration Times [51.61278695776151]
Federated Learning (FL) is well known for its privacy protection when training machine learning models among distributed clients collaboratively.
Recent studies have pointed out that the naive FL is susceptible to gradient leakage attacks.
Differential Privacy (DP) emerges as a promising countermeasure to defend against gradient leakage attacks.
arXiv Detail & Related papers (2021-01-11T19:43:12Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.