Port 3055: Policy Server — A Registered Ghost

What Port 3055 Is

Port 3055 sits in the registered port range (1024–49151). These ports are assigned by IANA — the organization that manages the Internet's numbering systems — to specific applications and services. Unlike the well-known ports below 1024, registered ports don't require root privileges to open, and the assignments are first-come, first-served rather than governed by standards bodies.

The IANA registry lists port 3055 as "policyserver" — registered to Mark Garti at Sonus Networks, for a service called "Policy Server." That's the entire public record.

What Sonus Networks Is

Sonus Networks (now Ribbon Communications) built VoIP infrastructure — session border controllers, media gateways, and soft-switch systems deployed at carriers and large enterprises. Their flagship policy product, the PSX (Policy Switch Exchange), handled routing decisions and quality-of-service policy for large-scale voice networks. Port 3055 was likely reserved for internal communication within that system.

No public protocol documentation exists. No RFC was filed. The port never appeared in any IETF working group. It's a proprietary registration for proprietary equipment.

Why This Matters

The registered port range contains thousands of entries like this one: a company claimed a port, shipped a product that used it, and left behind nothing but a name in a registry. Some of those products still run in production today. Most don't.

If you're seeing traffic on port 3055, it's almost certainly one of three things:

1. Legacy Sonus/Ribbon infrastructure in your environment
2. An application that chose this port informally (developers sometimes pick obscure registered ports to avoid collisions)
3. Port scanning or probing traffic

How to Check What's Using This Port

On Linux or macOS:

# See what process is listening on port 3055
ss -tlnp | grep 3055

# Or with lsof
lsof -i :3055

On Windows:

netstat -ano | findstr :3055
# Then look up the PID in Task Manager, or:
Get-Process -Id (Get-NetTCPConnection -LocalPort 3055).OwningProcess

If nothing is listening, the port is simply unused on your system. That's the normal state for the vast majority of registered ports at any given moment.