bkg-ntrip-client-image

Container image for the BKG NTRIP Client (BNC) built from official source. BNC is a software package for receiving, processing, and broadcasting GNSS data streams via NTRIP (Networked Transport of RTCM via Internet Protocol).

Features

• NTRIP Client: Receive GNSS correction data from NTRIP casters
• NTRIP Server: Re-broadcast NTRIP streams to other clients
• RINEX v3 Output: Generate RINEX 3 observation files with configurable intervals
• Skeleton File Support: Use template files for proper RINEX header structure
• Headless Operation: Runs without GUI, suitable for containerized deployments

Quick Start

NTRIP Client Mode

Receive NTRIP streams and generate RINEX files:

docker run -d --rm \
  -v $(pwd)/bnc-client.conf:/srv/bnc/conf/bnc.conf \
  -v $(pwd)/rnx:/srv/bnc/rnx \
  -v $(pwd)/logs:/srv/bnc/logs \
  bnc:latest

NTRIP Server Mode (Client + Server)

Receive streams from a caster and re-broadcast them:

docker run -d --rm -p 2101:2101 \
  -v $(pwd)/bnc-server.conf:/srv/bnc/conf/bnc.conf \
  -v $(pwd)/rnx:/srv/bnc/rnx \
  -v $(pwd)/logs:/srv/bnc/logs \
  bnc:latest

Configuration

Configuration Files

• bnc-client.conf: Client-only configuration (receives streams, generates RINEX)
• bnc-server.conf: Server configuration (receives and re-broadcasts streams)

Key Configuration Options

NTRIP Client Settings

# Enable NTRIP client
ntripClient=1
ntripVersion=2

# NTRIP caster URL
casterUrlList=http://user:pass@caster.example.com:2101

# Mountpoints (format: //user:pass@host:port/mountpoint format country lat lon no 2)
mountPoints=//user:pass@caster.example.com:2101/MOUNTPOINT RTCM_3 NZL -41.20 174.93 no 2

NTRIP Server Settings

# Enable NTRIP server (for re-broadcasting)
ntripServer=1
ntripServerPort=2101

RINEX Output Settings

# RINEX v3 output
rnxV3=2
rnxV3filenames=2

# Output directory
rnxPath=/srv/bnc/rnx

# Interval (15 minutes)
rnxIntr=15 min

# Sampling rate (1 second)
rnxSampl=1

# Use skeleton file as template (0 = optional, 1 = required)
rnxOnlyWithSKL=0

# Skeleton file
rnxSkel=SKL

Skeleton Files

Skeleton files (.SKL) are RINEX header templates that define the observation types and station metadata. Place skeleton files directly in the RINEX output directory.

Example: For mountpoint AVLN00NZL0, create rnx/AVLN00NZL.SKL (or /srv/bnc/rnx/AVLN00NZL.SKL inside the container)

The skeleton file should contain a valid RINEX 3 header with:

• Marker name
• Receiver and antenna information
• Observation types for each GNSS system (GPS, GLONASS, Galileo, BeiDou, etc.)
• Approximate position

Volume Mounts

Volume	Description	Required
/srv/bnc/conf	Configuration files	Yes
/srv/bnc/logs	Log files	Recommended
/srv/bnc/rnx	RINEX output files and skeleton files (.SKL)	Recommended

Examples

Example 1: Simple Client

# Create directories (skeleton files go directly in rnx/)
mkdir -p logs rnx

# Run container
docker run -d --rm \
  --name bnc-client \
  -v $(pwd)/bnc-client.conf:/srv/bnc/conf/bnc.conf \
  -v $(pwd)/rnx:/srv/bnc/rnx \
  -v $(pwd)/logs:/srv/bnc/logs \
  bnc:latest

# Check logs
docker logs bnc-client
cat logs/bnclog_*

# Check RINEX files (after first interval)
ls -lh rnx/

Example 2: Server with Port Mapping

# Run server (exposes port 2101)
docker run -d --rm \
  --name bnc-server \
  -p 2101:2101 \
  -v $(pwd)/bnc-server.conf:/srv/bnc/conf/bnc.conf \
  -v $(pwd)/rnx:/srv/bnc/rnx \
  -v $(pwd)/logs:/srv/bnc/logs \
  bnc:latest

# Connect to server from another client
# Use: your-host:2101 as the caster URL

Troubleshooting

No RINEX Files Generated

1. Check logs: docker logs <container-name> or cat logs/bnclog_*
2. Verify stream connection: Look for "1 stream(s)" in logs
3. Check permissions: Ensure rnx directory is writable
4. Wait for interval: RINEX files are created at the configured interval (default: 15 minutes)

Permission Errors

The container automatically fixes permissions for mounted volumes. If you see permission errors:

# Fix permissions on host (if needed)
sudo chown -R 1000:1000 logs rnx

Skeleton File Not Found

• Ensure skeleton file name matches mountpoint name
• Check skeleton file is in the rnx/ directory (or /srv/bnc/rnx/ inside container)
• Verify rnxSkel path in configuration (use . for same directory as RINEX files, or absolute path like /srv/bnc/rnx)

No Streams Configured

Check your mountPoints configuration format:

mountPoints=//user:pass@host:port/MOUNTPOINT format country lat lon no 2

All fields are required. Example:

mountPoints=//user:pass@caster.com:2101/STATION RTCM_3 NZL -41.20 174.93 no 2

Building

docker build -t bnc:latest .

References

• BKG NTRIP Client Documentation
• RINEX Format Specification
• NTRIP Protocol