Kolmogorov-Smirnov two-sample tests on packet-size distributions and inter-packet timing show that standard Rook (altering ~1-in-10 packets) is statistically indistinguishable from normal TF2 gameplay across 20 samples each. High-bandwidth Rook (1-in-2 packets) shows a slightly higher average bandwidth but remains difficult to distinguish on traffic-shape metrics.

Rook constructs per-field symbol tables by observing 600 packets (~60 seconds) of real gameplay at session start, then restricts substituted values to only those previously observed with frequency within two orders of magnitude of the median. This ensures altered packets never contain field values that are absent or anomalously rare in legitimate traffic, defeating value-anomaly and out-of-range DPI filters.

§2.6 defense

Rook achieves 34 bits/second client-to-server and 26 bits/second server-to-client within Team Fortress 2, sufficient for OTR-encrypted real-time chat. Rook use did not trigger Valve Anti-Cheat warnings and did not noticeably degrade gameplay for co-located legitimate players.

§4.1 defense

Because Rook runs the actual game client and server rather than mimicking them, active anti-mimicry probes receive identical responses to a normal game instance. Systems based on protocol mimicry are vulnerable to probes that expose non-conforming behavior, but Rook eliminates this attack surface entirely.

§4.2 Anti-Mimicry defense

Game-specific trigram analysis of mutable fields distinguishes high-bandwidth Rook (1-in-2 substitution rate) in server-side packet counts, showing clearly reduced distinct-trigram counts versus baseline. Standard Rook (1-in-10) produces only a few outliers and is not reliably distinguishable; any detector would face a high false-negative or false-positive rate against normal-rate Rook.

§4.3 Game-Specific n-gram Analysis evaluation

A three-stage detection pipeline exploiting the "dual-role" behavioral fingerprint of single-IP circumvention relays achieved 23.2% recall (96/414 ground-truth relays) with a 0.18% false-positive rate against 97,651 benign TLS servers, for an overall accuracy of 99.5%. The ground-truth set covered OpenVPN, WireGuard, and SOCKS relays identified in a 17 TB single-day backbone trace (WIDE Project, April 9, 2025).

2026-almutairi-server §3.4, Table 1 traffic-shapedpiflow-correlation

The paper identifies a fundamental architectural vulnerability in single-IP circumvention designs: a relay must generate new observable flows (via DNS or TLS SNI) to reach end services after receiving client connections, creating a detectable server-and-client behavioral contrast. A relay accessing user-facing domains (news, social media) scores high on a Relay Suspicion Score (w=0.9) versus infrastructure domains (w=0.1). The paper argues this host-level signal is censorship-invariant and cannot be concealed by link obfuscation.

2026-almutairi-server §2.4, §4 traffic-shapedpisni-blocking

AnyTLS's default padding scheme operates across 8 levels (stop=8), with initial padding fixed at 30 bytes, small-data padding 100–400 bytes, and medium-to-large data padding chains of 400–500 bytes continuing through multiple 500–1000 byte segments. The 'c' (continue) marker allows multi-stage padding sequences within a single connection burst.

2026-anon-anytls-anytls-sing-box-2026 §2.3 traffic-shapedpi

AnyTLS is a TLS-based proxy protocol maintained by the sing-box team, designed in 2024 and first released in the sing-box dev-next branch. Its core mechanism wraps arbitrary proxy traffic in standard TLS and applies a configurable padding scheme (Padding Scheme) to enhance traffic concealment while maintaining compatibility with standard TLS infrastructure.

2026-anon-anytls-anytls-sing-box-2026 §1.1–1.3 tls-fingerprinttraffic-shapedpi

Simulations extending the ENEM19 game-theory framework show that ephemeral proxy schemes (modeled on Snowflake/Lantern) effectively neutralize both the "optimal" and "aggressive" censors from the original framework. In overprovisioned settings (proxies arriving at 250/step vs. 200 clients/step), even the null censor scenario outperforms either censor in equal-arrival settings. Over 90% of waiting users receive a proxy within 1 time step. The critical variable is not censor sophistication but proxy arrival rate relative to client demand—high proxy churn combined with high arrival rate defeats both enumeration strategies tested.

2026-fares-game §4, Fig 1, Fig 2, Table 1 dpitraffic-shape

WebSocket, required by HTTPT and WebTunnel to establish covert channels inside TLS connections, had an adoption rate as low as 6.3% of websites in 2021, sharply limiting the pool of volunteer websites that can act as proxies for these tools. By contrast, Huma's traffic replacement scheme embeds covert data in standard HTTP leaf objects (images, scripts, CSS), requiring only that the DW serve HTTP content — a near-universal property.

2026-kamali-huma §II-C dpitraffic-shape