Port 1973Data Link Switching Remote Access Protocol

Carries Data Link Switching remote-access traffic over its assigned TCP and UDP service.

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

also known as dlsrap

Technical Details

what runs on :1973

Data Link Switching Remote Access Protocol is registered on port :1973 over tcp and udp to Steve T Chiang. 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 :1973

this machine

# linux
sudo ss -tulpn 'sport = :1973'

# macos / bsd
sudo lsof -nP -i :1973

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :1973

another host

nmap -sV -p T:1973 <host>
sudo nmap -sU -sV -p U:1973 <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 :1973

risk score

1/ 10safe

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

remote access averages 3.7 across 197 ports — this one sits 2.7 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 :1973 yet

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

Record

iana registry entry

port: :1973
service: Data Link Switching Remote Access Protocol
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 1/10safe
category: Remote Access Network Services
usage: The dlsrap assignment identifies the Data Link Switching Remote Access Protocol on TCP and UDP port 1973. IANA records the assignment to Steve T Chiang, but provides no additional deployment or product details.
lookups: 0rank 993
added: 2026-09-11
updated: 2026-09-11
references: IANA service name registry — port 1973

Something wrong?

This record is maintained by the engineers who use port 1973. 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 2026-09-11.

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 197 in remote access →

the 8 most looked-up other ports in remote access — 197 ports carry that label.

port	service	proto	category	risk	views
:8000	Intel Remote Desktop / Alternate HTTP Port	TCP	Web Services	safe	84.3k
:8888	D2GS Admin Console	TCP	Remote Access	caution	83.7k
:8881	Atlasz Secure Server	TCP	Web Services	caution	67.6k
:5938	TeamViewer	TCPUDP	Remote Access	caution	65.0k
:8291	Winbox MikroTik Admin	TCP	Security	caution	62.9k
:8008	IBM HTTP Server Admin	TCP	Web Services	caution	58.3k
:135	Microsoft EPMAP	TCPUDP	Security	caution	51.9k
:23	Telnet	TCP	Remote Access	caution	34.8k

risk mix of the 8 listed

safe13%
caution88%

0 of 8 encrypted

Port :1973Data Link Switching Remote Access Protocol

Technical Details

Security Information

Related Ports

Port 1973Data Link Switching Remote Access Protocol