Port 1672: netview-aix-12 — IBM NetView's Open Topology Stream

What This Port Is

Port 1672 is registered to netview-aix-12 — a name that tells its own story. IBM needed not one port but twelve consecutive ones for their NetView network management platform on AIX (IBM's Unix operating system). They registered the whole block, 1661 through 1672, with IANA.

Port 1672 was the last of the twelve, assigned to the NetView Open Topology Stream — the channel over which NetView streamed live data about network topology to other management components.¹

The Block

IBM's twelve registered ports served distinct roles within the NetView architecture:¹

These were registered around the era of NetView's Mid Level Manager — a product aimed at giving large enterprises a centralized view of their entire network from AIX workstations.²

What NetView Was

IBM NetView for AIX was a serious piece of enterprise infrastructure in the 1990s. Large organizations — banks, manufacturers, government agencies — used it to monitor routers, switches, and servers across sprawling networks. It spoke SNMP, drew network maps, and alerted administrators when things broke.

Port 1672 specifically served the Open Topology Stream: a mechanism for propagating network topology information (which nodes exist, how they're connected, what changed) between components of the NetView system. When a new device appeared on the network or a link went down, that information flowed through this port to wherever it needed to go.

Current Status

NetView for AIX is a legacy product. IBM eventually folded network management capabilities into Tivoli Network Manager and other platforms. Few organizations run the original NetView for AIX today.

Port 1672 is registered with IANA and appears in these registries as netview-aix-12, but it carries no traffic on modern networks unless someone is running very old IBM infrastructure. No known malware or trojans use this port.

Checking What's on This Port

If you see activity on port 1672 and want to know what's using it:

Linux/macOS:

sudo ss -tlnp | grep 1672
# or
sudo lsof -i :1672

Windows:

netstat -aon | findstr :1672

If something is listening on 1672 on a modern system, it's almost certainly not NetView — it's an application that chose this port for its own reasons, or something worth investigating.

Why Unassigned-in-Practice Ports Matter

Port 1672 illustrates something real about the registered port range: registration doesn't mean active use. IANA's registry is a historical record as much as a live map. Ports get registered by companies for products that eventually fade. The registration stays. The traffic doesn't.

This is why the registered range (1024–49151) is both useful and noisy. It's useful because the assignments prevent collisions between software that's actually in use. It's noisy because thousands of entries represent products that no longer ship, companies that no longer exist, or protocols that never caught on.

Port 1672 is a small piece of IBM's network management history — twelve consecutive numbers that a team of engineers needed, registered with IANA so they wouldn't collide with anyone else, and now quiet.