{
  "port": 1600,
  "protocol": "tcp",
  "service": "issd",
  "oneLiner": "Registered as \"issd\" with no attribution and no known implementation.",
  "whatItIs": "IANA assigns 1600 (TCP and UDP) to \"issd\", one of a handful of registry entries that carry no contact, no description beyond the name, and no reference. No mainstream software binds it. In practice a round number like 1600 is far more likely to be someone's hand-picked application or test port than anything to do with the registration.",
  "exposure": {
    "verdict": "careful",
    "note": "Treat an open 1600 as a locally chosen port of unknown provenance — the registry name gives you no security properties to reason from."
  },
  "checkCommand": "nc -vz -w 3 TARGET 1600",
  "links": [
    {
      "title": "IANA port registry — 1600",
      "url": "https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=1600",
      "kind": "iana"
    }
  ]
}