{
  "port": 1687,
  "protocol": "tcp",
  "service": "nsjtp-ctrl",
  "oneLiner": "The control channel of Netscape's Java Transaction Protocol — a dead product's registration.",
  "whatItIs": "IANA registers 1687 as \"nsjtp-ctrl\" (TCP and UDP), the control half of Netscape's JTP, paired with \"nsjtp-data\" on 1688. It belonged to Netscape's application-server line, which passed through iPlanet and Sun and no longer exists. There is no current implementation and no public specification, so the registration is historical only.",
  "exposure": {
    "verdict": "careful",
    "note": "Nothing in current use binds 1687, so an open port here is an unidentified listener that needs to be traced to a process before you judge it."
  },
  "checkCommand": "nc -vz -w 3 TARGET 1687",
  "links": [
    {
      "title": "IANA port registry — 1687",
      "url": "https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=1687",
      "kind": "iana"
    }
  ]
}