Port 406 — imsp

Well-known port 406 (tcp/udp): Interactive Mail Support Protocol. Service name: imsp.

port kind port status standard verification verified tier A iana-registry-row@1

registry record

value: 406

Service Name	imsp
Port Number	406
Transport Protocol	tcp
Description	Interactive Mail Support Protocol
Assignee	[John_Myers]
Contact	[John_Myers]
Registration Date
Modification Date
Reference
Service Code
Unauthorized Use Reported
Assignment Notes

source: https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.csv
version: IANA registry, Last-Modified: Fri, 29 May 2026 01:11:28 GMT
retrieved: 2026-05-29 · updated: 2026-05-29

agent: curl -H 'accept: application/json' wire.phall.io/port/406 or /port/406.json