Port 3751CommLinx GPRS Cube

Port 3751 is assigned to the CommLinx GPRS Cube service over TCP and UDP.

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

Technical Details

what runs on :3751

CommLinx GPRS Cube is registered on port :3751 over tcp and udp to Peter Johnson, assigned April 2003. 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 found open rarely. What's listening is often not the registered service, so check before you assume.

find what's listening on :3751

this machine

# linux
sudo ss -tulpn 'sport = :3751'

# macos / bsd
sudo lsof -nP -i :3751

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :3751

another host

nmap -sV -p T:3751 <host>
sudo nmap -sU -sV -p U:3751 <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 :3751

risk score

1/ 10safe

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

mobile averages 2.2 across 65 ports — this one sits 1.2 below.

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 :3751 yet

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

Record

iana registry entry

port: :3751
service: CommLinx GPRS Cube
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 1/10safe
category: Mobile
usage: TCP and UDP port 3751 is assigned to CommLinx GPRS Cube. The assignment is registered to Peter Johnson, but public protocol and deployment details are not established.
lookups: 0rank 993
added: 2026-09-05
updated: 2026-09-05
references: IANA service name registry — port 3751

Something wrong?

This record is maintained by the engineers who use port 3751. 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 2026-09-05.

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

all 65 in mobile →

the 8 most looked-up other ports in mobile — 65 ports carry that label.

port	service	proto	category	risk	views
:8882	Atlasz Secure App Server	TCP	Web Services	caution	66.9k
:2082	Infowave Mobility	TCP	Network Services	caution	17.7k
:3386	GTP (GPRS Tunneling Protocol)	TCPUDP	Network Services	caution	16.7k
:7401	RTPS DDS Traffic	TCPUDP	Network Services	safe	14.7k
:2948	WAP Push MMS	TCPUDP	Network Services	safe	11.7k
:5222	XMPP Client Connection	TCP	Network Services	caution	11.7k
:3006	Miralix SMS Connector	TCP	Mobile	caution	11.3k
:2949	WAP Pushsecure MMS	TCPUDP	Cloud	safe	10.4k

risk mix of the 8 listed

safe38%
caution63%

0 of 8 encrypted

Port :3751CommLinx GPRS Cube

Technical Details

Security Information

Related Ports

Port 3751CommLinx GPRS Cube