Port 33331DiamondCentral Interface

TCP and UDP port 33331 is assigned to the DiamondCentral Interface; no established public usage is known.

transport: tcp · udp
in transit: cleartext
assignment: official
risk: 1/10
lookups: 0

also known as diamondport

Technical Details

what runs on :33331

DiamondCentral Interface is registered on port :33331 over tcp and udp to Edward Browdy, assigned July 2002. We don't have a technical write-up for it beyond the IANA registry entry.

In nmap's internet-wide scan data this port is never observed open, so if it's open on your network it's more likely a custom or misconfigured service than the registered one.

find what's listening on :33331

this machine

# linux
sudo ss -tulpn 'sport = :33331'

# macos / bsd
sudo lsof -nP -i :33331

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :33331

another host

nmap -sV -p T:33331 <host>
sudo nmap -sU -sV -p U:33331 <host>

run it? the handshake, the implementations you meet in the wild and the flags that matter come from the engineers who do.

add technical details

Security Information

exposure of :33331

risk score

1/ 10safe

routine exposure. this port is rarely the way in on its own — keep it patched and logged and move on.

in transit

cleartext

credentials and payloads are readable by anyone on path

assignment

official

registered with iana for this service — scanners fingerprint it by number

reachable over

tcp · udp

udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite

security overview

no security notes recorded for :33331 yet

known exploits, hardening advice, what a compromise looks like — suggest an edit if you know its exposure.

Record

iana registry entry

port: :33331
service: DiamondCentral Interface
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 1/10safe
category: uncategorised
usage: IANA assigns TCP and UDP port 33331 to the DiamondCentral Interface, registered to Edward Browdy in 2002. No widely established implementation or common deployment is known.
lookups: 0rank 993
added: 2026-10-20
updated: 2026-10-20
references: IANA service name registry — port 33331

Something wrong?

This record is maintained by the engineers who use port 33331. Every field on it is editable — change what's wrong, say how you know, and a reviewer publishes it, usually within a minute. Last touched 2026-10-20.

01edit any field on a page of its own
02a model checks it for accuracy and spam
03clean and confident goes live immediately

edit this record →back to the registry

Related Ports

browse categories →

ports registered around :33331, by lookups.

port	service	proto	category	risk	views
:33333	Digital Gaslight Service	TCP	—	safe	0
:33334	SpeedTrace TraceAgent Discovery	UDP	Network Services	safe	0

risk mix of the 2 listed

safe100%

0 of 2 encrypted

Port :33331DiamondCentral Interface

Technical Details

Security Information

Related Ports

Port 33331DiamondCentral Interface