Knowledge Base

VLF Knowledge Base

VLF Proto: runtime gateway with QUIC/TCP fallback

Core VLF Proto idea: the [VLF] tag enables automatic external transport behavior. The client chooses a working path and switches without manual protocol toggling.

Published: February 25, 2026

Problem

We needed a real operational gateway, not a demo tunnel: stable behavior under bad networks, clear diagnostics, and deployable server workflow.

Architecture

  • RELAY lane: HTTP polling path for TCP/web traffic.
  • SESSION QUIC lane: primary control + TCP streams + UDP datagrams.
  • SESSION TCP lane: fallback when UDP/QUIC is blocked.

Important: local tunnel stays on device, while external path is selected dynamically (QUIC -> TCP session -> relay).

Why this is useful

  • No manual protocol selection for the user.
  • Fallback chain is runtime logic, not operator hotfix.
  • Install/update scripts and systemd hardening make operations predictable.

Bench snapshot

From proto_bench report (pre-alpha):

  • TCP throughput: 2.61 Mbps (PASS by threshold).
  • UDP loss: 0.00%, jitter: 0.73 ms (PASS).
  • Concurrency and fallback: 10/10 success.

Ops commands

curl -fsSL https://raw.githubusercontent.com/skalover32-a11y/VLF-Proto/main/scripts/install.sh | sudo bash -s -- sudo bash /opt/vlf-proto/scripts/update.sh --ref main systemctl status vlf-gateway --no-pager