RDEM Systems / Operator NotesStratum 1 · GNSS · NTSENFR
NTP test & audit toolkit · No signup · No telemetry
Online NTP Validator — Test NTP servers & validate compliance.
Test any NTP server (public or RFC 1918 private) against our GNSS-disciplined Stratum 1 references — then turn the results into audit evidence for ISO 27001 A.12.4.4, NIS 2 Art. 21, PCI-DSS Req. 10.6 and DORA.
Built and operated by Richard Demongeot — running NTP infrastructure since 2005, Pontoise, France.
Test Mode Selection
Three test modes — pick the one matching your scope. All produce evidence aligned with ISO 27001 A.12.4.4, NIS 2 Art. 21 and PCI-DSS Req. 10.6.
Basic Time Test
Browser-side check of your system time vs Stratum 1 GNSS. Audit-ready report.
NTP Bridge Test (RFC 1918)
Test internal NTP servers on private networks (10/8, 172.16/12, 192.168/16).
CLI Testing Script
Bash script for server-side compliance verification and evidence collection.
Basic Time Test
Test your system time against RDEM GNSS-disciplined Stratum 1 references — a prerequisite for ISO 27001, NIS 2 and DORA audit trails.
Testing...
Validation successful. This test was powered by our Stratum 1 GNSS references.
Test NTP servers on private address space (RFC 1918) without exposing them to the public Internet. Required for NIS 2 / ISO 27001 internal infrastructure reviews.
Bridge Not Connected
Start the local bridge to audit internal NTP infrastructure.
Quick Start:
# 1. Download and install
cd /tmp && curl -sL https://online-ntp-validator.com/bridge/ntp-bridge.tar.gz | tar xz
cd ntp-bridge && npm install
# 2. Start the bridge
node server.js
# Bridge running on ws://localhost:8080
# 1. Prerequisites: Node.js (via Homebrew if needed)
brew install node
# 2. Download and install
cd /tmp && curl -sL https://online-ntp-validator.com/bridge/ntp-bridge.tar.gz | tar xz
cd ntp-bridge && npm install
# 3. Start the bridge
node server.js
# Bridge running on ws://localhost:8080
# PowerShell - 1. Prerequisites: Node.js# Download from https://nodejs.org/# 2. Download the bridge
Invoke-WebRequest -Uri "https://online-ntp-validator.com/bridge/ntp-bridge.zip" -OutFile "$env:TEMP\ntp-bridge.zip"
Expand-Archive -Path "$env:TEMP\ntp-bridge.zip" -DestinationPath "$env:TEMP\ntp-bridge" -Force
cd "$env:TEMP\ntp-bridge"
# 3. Install and start
npm install
node server.js
# Bridge running on ws://localhost:8080
Download the bridge files using the curl commands above.
Testing...
CLI Testing Script
Bash script for server-side NTP testing and compliance verification — produces machine-readable output suitable for evidence collection during ISO 27001 and PCI-DSS audits.
# One-liner test
curl -sL https://ntp.rdem-systems.com/ntp-check.sh | bash
# Or download and run
wget https://ntp.rdem-systems.com/ntp-check.sh
chmod +x ntp-check.sh
./ntp-check.sh