Port 2206: HP OpenCall Bus — A Telecom Relic

Port 2206 is assigned to hpocbus — the internal communication bus of HP OpenCall, a telecommunications platform HP built for phone carriers. It operates on both TCP and UDP.

What HP OpenCall Was

HP OpenCall was a suite of software that phone companies used to run core services: voicemail, prepaid calling accounts, SMS routing, number portability, intelligent network features. Not the kind of software consumers ever saw — the kind that ran quietly inside carrier infrastructure while you dialed a number.

The platform shipped in several pieces: a media server for voice and video processing, a service controller for network logic, a signaling stack for SS7 (the protocol phone networks use to route calls), and subscriber mobility tools. These components talked to each other. Port 2206 was part of how they did it — the internal bus that passed messages between OpenCall services on the same system or across a local network.

HP OpenCall was deployed by carriers across North America, Europe, Asia, Africa, and Australasia, and was certified for use with switching equipment from Alcatel, AT&T, Ericsson, Fujitsu, Nokia, Nortel, and Siemens.¹

The Port Today

HP discontinued the OpenCall product line, including the Service Access Controller.² The software no longer ships. Port 2206 remains on the IANA registry — registrations don't expire when products do.

In practice, you won't encounter this port unless you're running legacy HP OpenCall infrastructure. If you see traffic on port 2206 and you're not running telecom equipment from the early 2000s, it warrants investigation.

Checking What's Listening

If port 2206 shows activity on your system:

# macOS/Linux
sudo lsof -i :2206

# Linux alternative
sudo ss -tlnp | grep 2206

# Windows
netstat -ano | findstr :2206

The process name in the output will tell you what's actually using the port.

What "Registered" Means

Port 2206 sits in the registered port range (1024-49151). These ports are not reserved by the operating system the way well-known ports (0-1023) are — any application can bind to them without special privileges. IANA maintains registrations to prevent collisions between software vendors, but the registry is advisory, not enforced.

A registered port for a discontinued product is not unusual. The IANA list is a historical record as much as a functional directory.