Port 180: RIS — A Ghost from the CAD Wars

Port 180 sits in the well-known range (0-1023), officially assigned by IANA to a service called "ris" — Intergraph. If you've never heard of it, you're not alone. This port is a fossil from the 1980s, when computer-aided design was young and every company built its own networking protocols.

What RIS Was

RIS — likely "Remote Intergraph Service" or similar — was a proprietary database connectivity protocol developed by Intergraph Corporation. In the world of CAD (computer-aided design) and GIS (geographic information systems), Intergraph was a pioneer. They understood distributed operations before most companies grasped what networking meant.

According to historical GIS documentation, RIS made connecting to a database "incredibly simple" in Intergraph's MGE (Modular GIS Environment) software.¹ In the early 1980s, Intergraph built communications systems with data concentrators that could transfer data at 2 Mbps over distances up to 6,000 feet — impressive for the era.²

Port 180 was their stake in the Internet's addressing system. Both TCP and UDP. A protocol for database linkages and remote services that powered engineering workstations across industries.

The Well-Known Range

Port 180 lives in the well-known port range (0-1023), which means it was assigned by IANA through formal processes — "IETF Review" or "IESG Approval."³ These ports were reserved in the Internet's early days when the protocol landscape was still being mapped out.

The assignment lists Dave Buehmann as the contact, though no date is specified. This was likely registered in the 1980s when Intergraph's networking stack was actively deployed.

What Happened to Intergraph

Intergraph was acquired by Hexagon AB in 2010 and still exists as a division.⁴ But RIS? The protocol vanished with the shift to open standards. Modern systems use TCP/IP directly, SQL protocols, REST APIs, and other interoperable technologies. Proprietary networking protocols from the 1980s didn't survive the standardization wave.

Port 180 remains officially assigned, but the service it was designed for is extinct. IANA doesn't typically reclaim these historical assignments — they serve as markers of what once was.

Security Note

Some older security databases flag port 180 as having been used by malware in the past.⁵ This is common for unused well-known ports — if a protocol dies but the port remains reserved, attackers sometimes repurpose it. If you see traffic on port 180 today, it's almost certainly not legitimate RIS traffic.

Checking Port 180

On Unix-like systems:

# See if anything is listening on port 180
sudo lsof -i :180

# Check for connections
sudo netstat -an | grep :180

On Windows:

# Check for connections
netstat -an | findstr :180

You probably won't find anything. Port 180 is a tombstone.

Why Unassigned (Dead) Ports Matter

The IANA registry is an archaeological record. Ports like 180 tell the story of the Internet's evolution — from a landscape of proprietary protocols to the open, interoperable system we have today.

Every reserved port represents a moment when someone needed to move data across a network and built something to do it. Some of those somethings — HTTP, SSH, DNS — became foundational. Others, like RIS, served their purpose and faded away.

Port 180 is a reminder that the Internet wasn't inevitable. It was built by companies and engineers trying to solve real problems, one protocol at a time. Most of those protocols are forgotten now. But the port numbers remain, quiet markers of what we built and left behind.