Local Signals#

Network‑Based Signals#

Network behavior is one of the strongest permissionless indicators of environmental conditions. The RTT‑App observes patterns that emerge during routine requests.

• DNS Resolution Variance — fluctuations in lookup time indicate instability or congestion.
• TLS Handshake Duration — longer or inconsistent handshakes suggest degraded paths or interference.
• QUIC Handshake Success and Fallback — repeated fallback to TCP/HTTP/2 reflects drift or loss.
• Protocol Negotiation — unexpected downgrades signal environmental inconsistency.
• Retry Patterns — increased retries imply packet loss or transient instability.
• Captive Portal Detection — redirects or blocked requests indicate constrained environments.

These signals require no special permissions and behave consistently across platforms.

Device‑Stability Signals#

The app can also observe local stability through standard lifecycle and runtime indicators.

• UI Thread Jank Metrics — frame drops and animation stalls reflect local load or contention.
• Memory Pressure Warnings — low‑memory conditions indicate local drift or resource strain.
• Thermal Throttling (Android) — thermal events reduce performance and signal environmental stress.
• Event Loop Jitter — irregular scheduling suggests instability in the local runtime.
• Foreground/Background Transitions — rapid or unexpected transitions can correlate with drift.

These signals do not reveal personal information and do not require system access.

Signal Characteristics#

Local signals share several important properties:

• Permissionless — all signals are available without user prompts or system privileges.
• Coarse but Reliable — they reflect environmental conditions without fine‑grained detail.
• Platform‑Stable — behavior is consistent across iOS and Android.
• Non‑Diagnostic — they indicate drift or clarity but do not identify root causes.
• Composable — each signal contributes independently to the Awareness model.

These characteristics make local signals ideal for RTT‑App v1.

Role in the Awareness Model#

Local signals form one half of the Awareness computation. They describe how the device “feels” right now. When merged with the server‑declared state, they produce a unified Awareness state that reflects both local and global conditions.