Port 2861: Dialpad Voice 2 — The Registered Port Nobody Knows About

What This Port Does

Port 2861 is registered with IANA¹ as Dialpad Voice 2 — a voice transport port for Dialpad, a cloud-based business communications platform. It supports both TCP and UDP.

Dialpad is a VoIP and unified communications service used by businesses for phone calls, video meetings, and messaging. The "Voice 2" designation suggests this is a secondary voice transport channel, likely used alongside port 2860 ("Dialpad Voice") for audio stream handling.

This port sits in the registered port range (1024–49151), where organizations and vendors apply to IANA to stake a claim on a number for their service. Unlike well-known ports (0–1023), registered ports don't require root/administrator privileges to bind, and their assignments are less universally enforced.

The Ghost Port Problem

Here's where it gets interesting: port 2861 is officially registered, but almost nobody knows it is. Search it in most port databases and you'll find one of three things:

• "Unassigned" (wrong)
• "Potentially malicious" (overcautious)
• Nothing at all

Security scanners routinely flag unknown open ports as suspicious, and 2861 is obscure enough that it often trips those alarms. If you see this port open on a machine running Dialpad, it's legitimate. If you see it on a machine that has never touched Dialpad, that's worth a closer look.

How to Check What's Using This Port

On macOS or Linux:

sudo lsof -i :2861

On Windows (Command Prompt, run as Administrator):

netstat -ano | findstr :2861
tasklist | findstr <PID>

On Linux with ss:

ss -tulnp | grep 2861

These commands will show you which process has bound to the port. If it's not a Dialpad-related process and you didn't expect anything to be there, investigate.

Why Unassigned (and Lightly-Assigned) Ports Matter

The registered port range has over 48,000 slots. IANA has assigned many of them, but enforcement is loose — applications can use any port they want, and plenty of software binds to registered ports that belong to someone else entirely.

Port 2861 is a good example of how the port numbering system works in practice: an application registers a number, uses it for its traffic, and the rest of the world barely notices the assignment exists. The registration matters for firewall rule authors and network administrators who need to know whether traffic on a given port is expected — but only if they know to check.

At a Glance