With the widespread adoption of graph-structured data, protecting the complex relational information between nodes and edges while preventing sensitive information leakage has become a critical challenge. However, existing edge protection methods either introduce noise directly into the adjacency matrix, resulting in significant information loss, or uniformly apply noise across all edges, leading to imbalanced privacy budget allocation and inefficiency. To address these issues, we propose DPEI, a Differential Privacy-based Edge Information protection solution designed to safeguard the edge relationships between two nodes, thus reducing the risk of privacy leakage and preventing attackers from repeatedly inferring internal community relationships from the released graph data. Specifically, DPEI achieves protection through PPO (Proximal Policy Optimization)based selection of locally optimal thresholds combined with adaptive Laplace noise operations, and attachment nodes below the threshold into high-information edges to enhance relational information protection. Subsequently, unlike traditional uniform allocation, DPEI distributes the privacy budget in proportion to the information content of each edge, ensuring that edges with higher information content receive stronger privacy protection. Extensive experiments conducted on three real-world graph datasets demonstrate that DPEI significantly outperforms existing methods across seven commonly used graph metrics, thereby validating its effectiveness and practicality.
Graph Neural Networks (GNNs) have shown considerable success in learning from graph-structured data, but their use in privacy-sensitive areas remains difficult because graph structure can leak sensitive link information. To satisfy edge-level differential privacy, a common approach is to inject noise into all elements of the graph's adjacency matrix, thereby obfuscating the existence of any single edge. However, stronger privacy requires more noise, and excessive noise reduces utility, making the privacy-utility balance a major barrier to practical privacy-preserving graph learning. To address this issue, we propose EdgeRefine, a local differential privacy framework that improves this trade-off through adaptive edge refinement. EdgeRefine first estimates edge-existence probabilities using Jaccard similarity and ranks edges for noisy edge removal. To ensure the sparsity and reliability of the final graph, it uses the privacy budget $\epsilon$ to determine the ratio of true to false edges, samples them separately based on this probability ranking, and controls the total number of edges with a separate sampling rate $k$. Extensive experiments show that EdgeRefine achieves accuracy comparable to the noise-free baseline and substantially outperforms other privacy-preserving methods across datasets and GNN architectures. Under privacy budget $\epsilon = 2.5$, EdgeRefine improves node classification accuracy over state-of-the-art baselines by 17.8\% on ACM under GAT and 19.7\% on Cora under GCN. In graph classification, it achieves an average accuracy degradation of around 5\% compared to the noise-free baseline. Under graph reconstruction attacks, EdgeRefine maintains relative absolute error levels above 1 across all privacy budgets, averaging 1.962 on Cora and 1.472 on AMAP, indicating strong resilience against privacy leakage.
Wenxiu Ding, Muzhi Liu, Zheng Yan et al.· 0 citations
Experiments on four benchmarks for node classification and link prediction show that PriDyG consistently outperforms geometrically decaying baselines under the same privacy budget and matches the utility of naive per-update retraining while reducing cumulative privacy cost by up to three orders of magnitude.
PPGNN, a personalized differentially private framework for decentralized graph data, enables user-specific privacy budgets during local perturbation while preserving analytical utility in decentralized graph learning scenarios.
Longzhu He, Peng Tang, Chaozhuo Li et al.· IEEE Transactions on Knowled...· 0 citations
A novel metric, ``Dependency Triad''(DT), is proposed, which summarizes the pairwise dependency information relevant to CPL using three parameters and yields a conservative estimator of pairwise CPL, which is particularly suitable for high-cardinality attributes.
Sandaru Jayawardana, S. Ulukus, Ming Ding et al.· 0 citations
CoP is proposed, a coordinated perturbation mechanism designed to mitigate CIL in multidimensional data collection while preserving utility and significantly outperforms state-of-the-art LDP mechanisms in reducing disclosure while preserving analytical accuracy.
Sandaru Jayawardana, Ming Ding, Kanchana Thilakarathna· Proceedings on Privacy Enhan...· 0 citations
SyntheGrAnon is introduced, a framework for evaluating synthetic graph anonymity that primarily targets the singling out, linkability, and inference risks outlined in the EU GDPR at the node and community levels, while also including edge-level attacks as an extension of the node-level setting.
Abele Malan, Ahmad Al Kurdi, Stefanie Roos et al.· Proceedings on Privacy Enhan...· 0 citations
