# cisco/joy

A package for capturing and analyzing network flow data and intraflow data, for network research, forensics, and security monitoring.

Repository: https://github.com/cisco/joy
Canonical: https://ross.abutalabs.com/products/joy
Language: C
License: NOASSERTION
License Family: other
Archived: true
Last push: 2024-04-01T09:50:44+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 3890, "days_push": 884, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1368, forks 334 (observed 2026-08-28T04:04:31.652045+00:00)

## What it is
Joy is a libpcap-based C package that captures network traffic and extracts flow and intraflow features (packet timing, byte distributions, TLS/DNS/HTTP details) into JSON. It includes analysis tools for network research, forensics, and security monitoring.

## Use cases
- capture and analyze network flow data as JSON
- fingerprint TLS traffic for security research
- monitor a small network for unwanted or unauthorized behavior
- extract features from pcap files for forensics
- study packet length and timing sequences within flows
- analyze DNS names and HTTP headers in traffic captures

## When to choose
- you need flow-oriented network feature extraction in JSON for research or forensics
- you want TLS fingerprinting and intraflow data from live traffic or pcap files
- you are doing security monitoring on a small network you administer

## When to avoid
- you need actively developed fingerprinting tools - the maintainers recommend Cisco Mercury instead
- you need large-scale production network monitoring rather than research-scale analysis
- you want a GUI-based traffic analyzer rather than a command-line tool

## Facets
- artifact type: cli-tool
- maturity: maintenance
- function: networking, security, analytics, monitoring
- domain: security, networking, developer-tools
- platform: cli
- tags: network-forensics, flow-analysis, tls-fingerprinting, pcap, json-output, traffic-analysis, linux, macos

## Member repositories
- cisco/joy (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:31.652045+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T04:41:03.003331+00:00, confidence not recorded.
  - readme: https://github.com/cisco/joy (fetched 2026-08-28T04:04:31.652045+00:00, sha ea484580a36e)
- Data as of 2026-08-30T08:39:29.467469+00:00.