Inter-arrival time sequences between client DoH/3 request packets retain site-specific temporal structure despite QUIC padding and stream multiplexing, exhibiting characteristic micro-burst and inter-burst gap patterns. Using timing features alone, LSTM achieves 83.75% ± 0.92% accuracy at 449 classes, and DoHFuse with its dual-branch DMAG-LSTM reaches 89.08% ± 0.49%, while length-only LSTM degrades to 8.95% under the same conditions.
From 2026-zhang-dohfuse-dual-branch-architecture — DoHFuse: A Dual-Branch Architecture with DMAGLSTM for Website Fingerprinting over DNS over HTTPS/3
· §IV.D; §V.B; §V.C; Table II
· 2026
· arXiv preprint
Implications
Adding inter-packet interval jitter (not just fixed padding) is critical: request-interval statistics and burst timing are the residual fingerprinting signal that survives EDNS(0) padding, so deliberate timing randomization must be layered on top of size obfuscation.
Covert channels that batch or coalesce DNS queries to flatten burst–gap patterns would directly degrade the discriminative features exploited by DoHFuse's temporal branch.