netpath 0.5.0

Network path analyzer: throughput, latency, and packet loss across AS paths

netpath

Network path analyzer: probe throughput, latency, and packet loss across Autonomous System (AS) paths. Runs mtr/traceroute to a target ASN, measures bidirectional iperf3 throughput to servers inside that ASN, and optionally overlays Cloudflare Radar RUM data for comparison.

Installation

pip install netpath

uvx netpath

uv tool install netpath

System Prerequisites

netpath relies on two external tools for path probing and throughput measurement. Install them before running:

• mtr — primary path prober (falls back to traceroute if unavailable)
• iperf3 — bidirectional throughput measurement (falls back to Cloudflare HTTP speedtest if unavailable)

# macOS
brew install mtr iperf3

# Debian / Ubuntu
sudo apt install mtr-tiny iperf3

# Fedora / RHEL
sudo dnf install mtr iperf3

Usage

Probe a specific ASN

netpath asn AS15169

Options:

-n, --count INTEGER       Max servers to test (default: 3)
-d, --duration INTEGER    iperf3 seconds per direction (default: 5)
-c, --cycles INTEGER      mtr probe cycles (default: 10)
--no-throughput           Skip throughput test, trace path only
--cf-token TEXT           Cloudflare API token (or set NETPATH_CF_TOKEN)
--json                    Output results as JSON

Probe top ASNs for a country

netpath country US

Options:

-t, --top INTEGER         Number of top ASNs to test (default: 10)
-n, --count INTEGER       Max servers per ASN (default: 3)
-d, --duration INTEGER    iperf3 seconds per direction (default: 5)
-c, --cycles INTEGER      mtr probe cycles (default: 10)
--no-throughput           Skip throughput test
--cf-token TEXT           Cloudflare API token (or set NETPATH_CF_TOKEN)

Examples

# Probe Google's ASN
netpath asn AS15169

# Probe top 5 UK ISPs
netpath country GB --top 5

# Path-only probe (no throughput test)
netpath asn AS7018 --no-throughput

# JSON output for scripting
netpath asn AS15169 --json | jq .verdict

Cloudflare Radar RUM Overlay

netpath can overlay Cloudflare Radar Real User Monitoring (RUM) quality metrics for each ASN, showing real-world HTTP performance data alongside your own measurements.

To enable it, pass a Cloudflare API token with radar:read permission:

export NETPATH_CF_TOKEN=your_token_here
netpath asn AS15169

Or pass it inline:

netpath asn AS15169 --cf-token your_token_here

Tokens are free. Create one in the Cloudflare dashboard with the radar:read permission scope.

License

MIT