Live Capture

hdds_viewer supports real-time DDS traffic capture via the HDDS Telemetry TCP protocol, enabling live monitoring and recording of DDS networks.

Overview

Live capture connects to an HDDS-enabled DDS participant and streams messages in real-time. This enables:

• Real-time traffic monitoring
• Live anomaly detection with ML
• On-the-fly QoS analysis
• Recording to .hddscap files

Connection Methods

HDDS Telemetry TCP

Connect to an HDDS participant's telemetry endpoint:

hdds-viewer --live --host 192.168.1.100 --port 7410

Default port: 7410

Local Domain

Monitor a local DDS domain:

hdds-viewer --domain 0

This creates a local participant that discovers and monitors traffic.

GUI Mode

Start Live Capture

1. Open hdds_viewer

2. File > Live Capture or press Ctrl+L

3. Configure connection:

- Host: Target IP or hostname

- Port: Telemetry port (default 7410)

- Domain: DDS domain ID (0-232)

4. Click Connect

Recorder Panel

Enable recording during live capture:

1. Open View > Recorder panel

2. Set output path (e.g., capture.hddscap)

3. Click Start Recording

4. Click Stop Recording when done

Recording statistics shown:

• Frames captured
• File size
• Duration
• Throughput (msg/s, MB/s)

CLI Mode

Monitor and Display

# Monitor domain 0, display to terminal
hdds-viewer --domain 0 --format text

JSON output for piping
hdds-viewer --domain 0 --format json | jq '.topic'

Statistics only
hdds-viewer --domain 0 --stats

Record to File

# Record with compression
hdds-viewer --domain 0 --record capture.hddscap --compress

Record with time limit
hdds-viewer --domain 0 --record capture.hddscap --duration 5m

Record with size limit
hdds-viewer --domain 0 --record capture.hddscap --max-size 1GB

Live Analysis

# Live ML detection
hdds-viewer --domain 0 --ml-detect

Live QoS monitoring
hdds-viewer --domain 0 --qos-alerts

Combined
hdds-viewer --domain 0 --ml-detect --qos-alerts --format json

Filtering

Topic Filters

# Single topic
hdds-viewer --domain 0 --topic SensorTopic

Regex pattern
hdds-viewer --domain 0 --topic-pattern "Sensor."


Multiple topics
hdds-viewer --domain 0 --topics SensorTopic,CommandTopic

# Filter by type name
hdds-viewer --domain 0 --type sensors::SensorData

# Filter by payload content (requires type info)
hdds-viewer --domain 0 --filter "data.value > 100"

# ~/.config/hdds-viewer/config.toml

[live]
default_host = "localhost"
default_port = 7410
default_domain = 0
auto_reconnect = true
reconnect_delay_ms = 1000

[capture]
default_path = "~/captures/"
compress = true
max_size = "10GB"
rotate = true
rotate_count = 5

[performance]
ring_buffer_size = 100000  # Message buffer
frame_batch_size = 100     # Frames per UI update
history_depth = 10000      # Frame table limit

Client                              Server (HDDS Participant)
   |                                     |
   |  ---- TCP Connect (port 7410) ---->|
   |                                     |
   |  <---- HELLO (version, caps) ------|
   |                                     |
   |  ---- SUBSCRIBE (topics, QoS) ---->|
   |                                     |
   |  <---- FRAME (topic, payload) -----|
   |  <---- FRAME (topic, payload) -----|
   |  ...                               |
   |                                     |
   |  ---- UNSUBSCRIBE ---------------->|
   |                                     |
   |  ---- CLOSE ---------------------->|

use hdds::prelude::;

let participant = DomainParticipant::builder()
    .domain_id(0)
    .with_telemetry(TelemetryConfig {
        enabled: true,
        port: 7410,
        max_connections: 5,
    })
    .build()?;

Via Environment

HDDS_TELEMETRY_ENABLED=1 HDDS_TELEMETRY_PORT=7410 ./my_dds_app

Via Config File

# hdds.toml
[telemetry]
enabled = true
port = 7410
max_connections = 5
topics = ""  # Or specific list

Error: Connection refused (127.0.0.1:7410)

# Verify port is listening
netstat -tlnp | grep 7410

Check firewall
sudo ufw allow 7410/tcp

Connected to 192.168.1.100:7410
Waiting for messages... (0 received)

# Monitor all topics
hdds-viewer --domain 0 --topic-pattern "."

Check discovery
hdds-viewer --domain 0 --discovery-only

High CPU Usage

Warning: High message rate (>100k msg/s), enabling adaptive sampling

• Use CLI mode instead of GUI for high rates
• Enable recording and analyze offline
• Filter specific topics

# Record only, no display
hdds-viewer --domain 0 --record capture.hddscap --quiet

Security

TLS Support (Enterprise)

hdds-viewer --live --host secure.example.com --port 7410 --tls \
  --cert client.crt --key client.key --ca ca.crt

Authentication

[live.auth]
method = "token"
token_env = "HDDS_VIEWER_TOKEN"

Best Practices

1. Use recording for analysis - Live ML detection adds latency; record first, analyze later for best results

2. Filter aggressively - On busy networks, filter to specific topics of interest

3. Monitor resource usage - Watch memory with --stats flag on long captures

4. Use compression - Always enable --compress for recording to save disk space

5. Air-gapped networks - Use --no-network flag to ensure no external connections