When a VPN Says "Connected" but Traffic Is Dead: Building Adaptive Connect 2.0

Описание и применение

В статье описывается, как проект Colitu столкнулся с проблемой, когда VPN показывает «подключено», но трафик перестает проходить через туннель. Решение Adaptive Connect 2.0 включает проверку реального трафика, хранение истории по сети, резервный мониторинг состояния и ограниченные параллельные попытки подключения, что позволило достичь 98,8 % успешных запросов в тесте с 11 инъекцией сбоев.

Задача

A VPN can display a connected indicator while application traffic stops flowing after 30–50 seconds, even though the TCP tunnel remains open.

Результат

Adaptive Connect 2.0 achieved a 98.8% HTTP probe success rate over 60 minutes with 11 injected faults, maintaining connectivity during a 101‑second primary server outage and limiting interruptions to ~5 seconds.

Рабочий процесс

• Measure server latency
• Select server
• Establish tunnel
• Verify real traffic via external endpoints
• Report connection as functional only after traffic passes
• Maintain bounded local history per network
• Use backup route only when primary fails
• Track primary and effective health separately
• Parallel probe best candidates with bounded retries
• Inject faults to test resilience

Доказательства

A VPN can establish a tunnel, complete its handshake, display a reassuring green Connected indicator, and still fail at its most important job: carrying traffic.

Источник

Adaptive Connect 2.0 treats a connection as functional only after useful traffic successfully passes through the selected tunnel.

Источник

In the 60‑minute endurance test, we used eight servers and injected 11 controlled failures lasting roughly 60–120 seconds each. An HTTP probe was sent through the VPN approximately every five seconds.

Источник

Successful HTTP probes 741 / 750, HTTP probe success rate 98.8%

Источник