Cyber-Resilient Digital Twins: Discriminating Attacks for Safe Critical Infrastructure Control
Authors: Mohammadhossein Homaei, Iman Khazrak, Rubén Molano, Andrés Caro, Mar Ávila
Organizations: Departamento de Ingeniería de Sistemas Informáticos y Telemáticos, Universidad de Extremadura, Av. Universidad S/N, Escuela Politécnica, Cáceres, 10003, Extremadura, Spain · Department of Computer Science, Bowling Green State University, Bowling Green, 43403, OH, USA
Industrial Cyber-Physical Systems (ICPS) face growing threats from cyber-attacks that exploit sensor and control vulnerabilities. Digital Twin (DT) technology can detect anomalies via predictive modelling, but current methods cannot distinguish attack types and often rely on costly full-system shutdowns. This paper presents i-SDT (intelligent Self-Defending DT), combining hydraulically-regularized predictive modelling, multi-class attack discrimination, and adaptive resilient control. Temporal Convolutional Networks (TCNs) with differentiable conservation constraints capture nominal dynamics and improve robustness to adversarial manipulations. A recurrent residual encoder with Maximum Mean Discrepancy (MMD) separates normal operation from single- and multi-stage attacks in latent space. When attacks are confirmed, Model Predictive Control (MPC) uses uncertainty-aware DT predictions to keep operations safe without shutdown. Evaluation on SWaT and WADI datasets shows major gains in detection accuracy, 44.1% fewer false alarms, and 56.3% lower operational costs in simulation-in-the-loop evaluation. with sub-second inference latency confirming real-time feasibility on plant-level workstations, i-SDT advances autonomous cyber-physical defense while maintaining operational resilience.
Figures & tables
Approach
Physics Informed
Attack Taxonomy
Uncertainty Aware
Resilient Control
TranAD (2022) ( Tuli et al., 2022 )
✗
✗
✗
✗
LGAT (2025) ( Wen et al., 2025 )
✗
✗
✗
✗
CDT (2026) ( Homaei et al., 2026 )
✓
✗
✗
✗
DT-MPC (2025) ( Zhang et al., 2025 )
✗
✗
✗
✓
Secure RMPC (2025) ( Xie et al., 2025 )
✗
✗
✗
✓
i-SDT (Proposed)
✓ †
✓
✓
✓
Table 1: Comparison of i-SDT with State-of-the-Art Approaches
Table 3: Multi-class attack detection on SWaT (36 scenarios). All baselines evaluated via Linear Probing on frozen latent representations; this protocol structurally favours i-SDT whose encoder is natively regularised for taxonomy separation via MMD, and the reported gains should be interpreted accordingly. Bold = best, † = significant ( p<0.05 , paired bootstrap, 104 resamples). Evaluated on NVIDIA RTX 4070 (12 GB).
Method
Normal ( N )
Single-Stage ( AS )
Multi-Stage ( AM )
Overall
MTTD (s)
Prec.
Rec.
F1
Prec.
Rec.
F1
Prec.
Rec.
F1
FAR
F1A
OmniAnomaly ( Su et al., 2019 )
0.881
0.928
0.904
0.717
0.669
0.692
0.694
0.631
0.661
0.119
0.677
112.7
USAD ( Audibert et al., 2020 )
0.897
0.939
0.918
0.749
0.703
0.725
0.718
0.662
0.689
0.098
0.707
95.3
MTAD-GAT ( Zhao et al., 2020 )
0.916
0.954
0.935
0.803
0.774
0.788
0.771
0.738
0.754
0.081
0.771
81.6
TranAD ( Tuli et al., 2022 )
0.924
0.958
0.941
0.814
0.786
0.800
0.783
0.749
0.766
0.074
0.783
76.9
i-SDT ( γ=0.80 , Proposed)
0.958 †
0.976 †
0.967 †
0.887 †
0.864 †
0.875 †
0.871 †
0.842 †
0.856 †
0.042 †
0.866 †
51.4 †
Table 4: Multi-class attack detection on WADI (15 scenarios). Same Linear Probing evaluation protocol as Table 3 ; the same structural caveat applies. Results for γ=0.80 . Bold = best, † = significant ( p<0.05 ). Evaluated on NVIDIA RTX 4070 (12 GB).
Method
SWaT
WADI
MMD 2
Sil. Coeff.
MMD 2
Sil. Coeff.
OmniAnomaly ( Su et al., 2019 )
0.038
0.297
0.034
0.274
USAD ( Audibert et al., 2020 )
0.051
0.348
0.046
0.321
MTAD-GAT ( Zhao et al., 2020 )
0.069
0.433
0.063
0.411
TranAD ( Tuli et al., 2022 )
0.078
0.468
0.071
0.439
i-SDT (Proposed)
0.142 †
0.673 †
0.131 †
0.641 †
Table 5: ADE embedding separation of single- vs. multi-stage attacks (higher MMD = better).
Mitigation Strategy
SWaT (36 Attacks)
WADI (15 Attacks)
Drel
Safety Viol.
Trecovery (s)
Act. Sat.
Drel
Safety Viol.
Trecovery (s)
Act. Sat.
Immediate Shutdown
1.000
0%
3847
0%
1.000
0%
4231
0%
DT-MPC ( Zhang et al., 2025 )
0.614
6.9%
378
9.8%
0.639
8.1%
401
11.3%
i-SDT w/o Robust Margin
0.563
8.3%
412
12.5%
0.591
9.7%
438
14.2%
i-SDT (Full Robust MPC)
0.437 †
2.1% †
267 †
3.8% †
0.461 †
2.9% †
284 †
4.6% †
Target Objective
≤0.50
≤5%
<300
–
≤0.50
≤5%
<300
–
Table 6: Disruption mitigation and resilience (simulation-in-the-loop evaluation; see Section 3.1 ). Drel : normalized cost; Trecovery : recovery time.
Metric
Value
Notes
Training (Offline):
DT training time
2.8 hrs
SWaT, E=200 , early-stop
ADE training time
1.4 hrs
SWaT, E=150 , early-stop
Fine-tuning (10%)
0.5 hrs
New-plant adaptation
Inference (Online, per 1 Hz cycle):
DT inference (TCN + NMC=50 )
16.1 ms
50 stochastic fwd. passes
Table 7: Computational Performance on Evaluation Platform (Intel Core i9-14900K, NVIDIA RTX 4070 12 GB, 64 GB RAM, PyTorch 2.0, CUDA 11.8). All inference timings averaged over 103 consecutive cycles on the SWaT test set ( d=51 ). Edge deployment is reserved as future work (Section 6 ).
Table 9: Performance under random sensor dropout. p : fraction of sensors unavailable per step.
Configuration
F1A
FAR
No Transfer (Train on WADI)
0.866
0.042
Direct Transfer (Zero-shot)
0.647
0.183
Fine-tune 10% WADI Normal
0.782
0.089
Fine-tune 50% WADI Normal
0.831
0.061
Gap (10% Fine-tune)
-9.7%
+111.9%
Table 10: Cross-Domain Transfer (SWaT → WADI). Note: 9.7% gap indicates domain-specific tuning remains necessary despite physics priors; transfer learning reduces labeling burden by 90% but cannot eliminate it entirely.
Configuration
F1A
FAR
Drel
Safety Viol.
MTTD (s)
Notes
i-SDT (Full)
0.894
0.033
0.437
2.1%
43.7
Baseline
Physics Weight Ablation:
α0=0 (no mass balance)
0.853
0.067
0.512
3.8%
62.3
−4.6%
λp=0 (no pipe physics)
0.864
0.058
0.491
3.2%
58.1
−3.3%
α0=0.01
0.871
0.051
0.478
2.9%
53.1
−2.6%
α0=0.10
0.882
0.041
0.461
2.5%
48.2
−1.3%
Table 11: Comprehensive Ablation Study on SWaT
Method
Precision
Recall
F1
OmniAnomaly (2019) ( Su et al., 2019 ) ∗
0.938
0.821
0.876
USAD (2020) ( Audibert et al., 2020 ) ∗
0.946
0.837
0.888
MTAD-GAT (2020) ( Zhao et al., 2020 ) ∗
0.951
0.862
0.904
TranAD (2022) ( Tuli et al., 2022 ) ∗
0.957
0.874
0.914
LGAT (2025) ( Wen et al., 2025 ) ∗
0.961
0.891
0.925
i-SDT (Proposed)
0.967
0.918
0.942
Table 12: Comparison with recent SOTA on SWaT (binary detection, for contextual reference only ∗ ).
Department of Computer Science, FAST NUCES, Development Sector, Faisalabad, Pakistan · Department of Information Technology, Riphah International University, Faisalabad, Pakistan