Port 3227: dwnmshttp — A Ghost Assignment

What Range This Port Belongs To

Port 3227 sits in the registered ports range (1024-49151). These ports are not reserved by default — any process on your machine can bind to them — but IANA maintains a registry of assignments so that software vendors can claim a port for their product and avoid collisions.

Claiming a registered port doesn't require much. You submit a request to IANA, they check for conflicts, and the assignment goes into the registry. Whether your company survives long enough to matter is a separate question.

The Official Assignment: DiamondWave NMS Server

IANA assigned port 3227 to dwnmshttp — the HTTP interface for DiamondWave's Network Management System (NMS). DiamondWave was a telecom equipment company building optical networking gear in the early 2000s. Their NMS server used port 3227/TCP for its HTTP management interface.¹

DiamondWave is no longer an active company. The port assignment remains in the IANA registry anyway. That's how registered ports work: once assigned, the registry doesn't reclaim them when the assignee disappears. Port 3227 will say "dwnmshttp" in IANA's database indefinitely, even though no living product is listening on it.

The Citrix Framehawk Connection

Port 3227 falls inside the range 3224-3324 UDP, which Citrix uses for Framehawk — a UDP-based display protocol for virtual desktops over lossy or high-latency connections like mobile networks.²

Framehawk doesn't specifically target port 3227. It uses whichever available UDP port it can bind in that range, working up from 3224. Each concurrent session takes its own port. If you see UDP traffic on 3227 in a Citrix environment, Framehawk is the likely explanation — not a resurrected DiamondWave server.

Note: Citrix deprecated Framehawk starting with XenApp/XenDesktop 7.18 in favor of EDT (Enlightened Data Transport). If you're seeing traffic here on a modern Citrix deployment, verify whether Framehawk is actually still enabled.

How to Check What's Listening

macOS / Linux:

# Show which process is listening on port 3227
sudo lsof -i :3227

# Or with ss (Linux)
ss -tlunp | grep 3227

Windows:

# Show listening ports with process IDs
netstat -ano | findstr :3227

# Then look up the PID
tasklist | findstr <PID>

If nothing comes back, nothing is listening. That's the expected result on most systems.

Why This Matters

The registered port range is a commons. When a vendor claims a port and then vanishes, that port isn't freed — it just becomes ambient noise in the registry. Security scanners, firewalls, and network monitoring tools still recognize these assignments.

If something unexpected is listening on 3227, it's worth investigating. An obscure or defunct port assignment is exactly the kind of quiet address an unauthorized service might hide behind — banking on the fact that no one will recognize the name "dwnmshttp" and think to look closer.