Open NTRIP Client

A free, open-source diagnostic client for NTRIP / RTK correction streams. One portable executable, no installer: drop it in a folder, connect to a caster, and see exactly what is happening on the wire - credentials, mountpoints, sourcetables, RTCM message flow, and the NMEA position handshake.

It is a clean-room successor to the Lefebure NTRIP Client: the same job (verify a caster is up, credentials work, a mountpoint streams, and geofencing accepts your position), rebuilt in Rust with the whole protocol conversation on one screen. No code was reused.

Status: 0.2.1, pre-release (pre-1.0).

Features

• NTRIP v1 and v2 (HTTP/1.1, chunked transfer) plus raw TCP straight to the byte stream.
• TLS with the bundled root store, and a loud diagnostic-only override for self-signed casters.
• Serial receiver forwarding over any COM port, with NovAtel auto-configuration.
• GGA position reporting for VRS and geofenced mounts, with an offline embedded city / ZIP geocoder.
• Four always-present diagnostic tabs - Event log, Connection log, RTCM3 Stream detail, and Sourcetable browser.
• Live RTCM3 inspector: per-message-type counts, rates, sizes, CRC and garbage-byte health.
• Sourcetable browser with STR / CAS / NET records, sorting, filtering, and one-click mount select.
• Live readouts (fix state, correction age, DOPs, satellites, speed) plus a stream-activity indicator.
• Event, NMEA, and raw-capture logging, all next to the exe.
• Portable single exe - no installer, no AppData, no registry.
• Headless --selftest for scripting and CI.

Download and install

Releases are built by the tag-triggered CI pipeline (.github/workflows/release.yml). Grab the latest from the releases page of the repository:

• Windows (primary): OpenNtripClient.exe - one file, no installer, no DLLs. The published exe is code-signed; verify the digital-signature tab in file Properties and check SHA256SUMS. SmartScreen may still show "Windows protected your PC" while the signing certificate builds reputation - choose More info -> Run anyway after verifying the signature. Unsigned CI or self-built binaries always trigger SmartScreen; that is expected.
• Linux / macOS: open-ntrip-client-<version>-linux-x86_64.tar.gz and open-ntrip-client-<version>-macos-arm64.tar.gz.

The app is portable by design: it writes settings, logs, and captures only to the folder it runs from - never AppData, never the registry. To move or back up an installation, copy the folder.

Quick start

1. Put OpenNtripClient.exe in a folder of its own (it writes its files there).
2. Coming from the Lefebure client? Copy your old Settings.txt / ntripconfig.txt into that folder first. The first run imports them into settings.toml and leaves the originals untouched.
3. In the NTRIP Caster panel, enter host / port / credentials, click Get Sourcetable, open the Sourcetable tab, pick a mountpoint, then click Connect.
4. Optional: in Receiver (Serial), pick your GNSS receiver's COM port and baud to forward corrections and watch the fix state. If the caster wants a position from you (a geofenced or VRS mount), set it up under GGA position reporting (city / ZIP / lat-lon).

Security note: caster passwords are stored in plaintext in settings.toml, exactly as the original stored them in ntripconfig.txt - the portable folder is the security boundary. Anyone who can read the folder can recover the credentials, so keep it off shared machines and shared drives if that matters for your caster account.

The interface

The whole client is a single window. Every region, the GGA handshake, and the diagnostic tabs are documented in the user guide.

Building from source

cargo build --release

The binary is OpenNtripClient.exe (Windows) or OpenNtripClient (elsewhere). The Rust toolchain is pinned by rust-toolchain.toml. Linux needs libudev-dev pkg-config libxkbcommon-dev libwayland-dev libgl1-mesa-dev.

If the repo lives on a network share, redirect the build directory to a local disk first - builds on SMB are slow and flaky. Use a repo-local, machine-local config (it is gitignored) so it applies to every shell and never leaks into your other cargo projects:

# .cargo/config.toml (create it in the repo root)
[build]
target-dir = "C:/cargo-target/open-ntrip-client"

The embedded geocoding database (crates/geodb/data/geo.bin) is committed, so a normal build needs no downloads and works offline. To regenerate it from fresh GeoNames / US Census data, see tools/geodb-gen.

Contributor docs live in docs/: one-surface.md (the UI layout law), design-guide.md (the Butter Paper theme), protocol-notes.md, parity-checklist.md, and signing.md.

Heritage and license

This project is a clean-room successor to the Lefebure NTRIP Client by Lance Lefebure - the tool that has served the GNSS community for well over a decade. The original is published free and its behavior inspired this rewrite; no code was reused. Thank you, Lance.

Licensed GPL-3.0-or-later. See LICENSE for the full text, CREDITS.md for data and font attributions (GeoNames CC BY 4.0, US Census public domain, embedded fonts), and THIRD-PARTY-LICENSES.md for the licenses of the statically linked Rust dependencies.