# WHATPORT(5221)

## NAME

port 5221 — 3eTI Extensible Management Protocol (3exmp) — The management channel of 3eTI ruggedized wireless gear — almost nothing else uses it.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA registered 5221/tcp in 2010 as 3exmp, the 3eTI Extensible Management Protocol for OAMP (operations, administration, maintenance, provisioning). 3e Technologies International builds hardened wireless and cybersecurity appliances for military and industrial networks, and the protocol carries device management for that equipment. UDP 5221 is reserved, not assigned. Outside a site running 3eTI hardware you will effectively never see this port open.

## EXPOSURE

**Do not expose.** This is a device management plane; it belongs on a management VLAN, never on an internet-facing interface.

## CHECK

```sh
nc -vz -w 3 TARGET 5221
```

## SEE ALSO

- iana — [IANA port registry — 5221 (3exmp)](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=5221) (iana.org)

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HTML: <https://whatport.net/5221/> · JSON: <https://whatport.net/5221.json> · full dataset: <https://whatport.net/ports.json>