Port 2651: EBInSite — A Name Without a Story

Port 2651 sits in the registered port range (1024–49151). These ports are not controlled by the operating system the way well-known ports below 1024 are — any user-level process can open one — but IANA maintains a voluntary registry so that software vendors can stake a claim and avoid collisions.

Someone staked a claim on port 2651. The service is called EBInSite, assigned to a contact named Lefteris Kalamaras, registered for both TCP and UDP. That is essentially everything that is publicly known about EBInSite.¹

The Ghost Registration

IANA's registered port range is full of entries like this. A developer or company submits a registration — the bar is low, it is voluntary, and there is no requirement to ship a product, write documentation, or tell anyone what the service does. The name lands in the registry. Then time passes.

EBInSite may have been:

• A proprietary enterprise product that never reached wide adoption
• Internal tooling that someone registered out of good practice
• A project that was planned and abandoned before launch
• Something that was popular in a narrow context and simply underdocumented

There is no RFC. There is no Wikipedia entry. There is no Stack Overflow thread. There is no archived product page. If EBInSite had users, they were quiet about it.

What This Means for Your System

If you see traffic on port 2651, it is almost certainly not EBInSite. The registered name is a historical artifact. What you are more likely looking at is:

• An application that chose this port arbitrarily or by internal convention
• A game, proxy tool, or developer service configured to use it
• A misconfigured or scanning process

To find out what is actually using it:

On Linux/macOS:

sudo ss -tlnp | grep 2651
# or
sudo lsof -i :2651

On Windows:

netstat -ano | findstr :2651
# Then look up the PID:
tasklist | findstr <PID>

Why Unrecognized Port Registrations Exist

The registered port range was never meant to be exhaustive or authoritative — it is a coordination mechanism, not an enforcement one. IANA's goal is to reduce accidental port collisions between legitimate software, not to certify what is running on any given machine.

The result is a registry with thousands of entries ranging from globally critical infrastructure (HTTPS at 443, SMTP at 25) to ghost registrations like EBInSite: a name, a contact, and silence.

If you encounter port 2651 in a security audit or network trace, treat it as unrecognized until you can identify the process. The IANA label provides no meaningful signal about what is actually there.