- Close the port if nothing on the host needs it.
- Identify the process that listens on it (commands below) before opening it in a firewall.
- Expose a service only to the networks that use it.
Port 3104: Autocue Logger Protocol
Port 3104 is assigned by IANA to autocuelog (Autocue Logger Protocol), autocuetime (Autocue Time Service).
How autocuelog works
Other servicesThe client sends a request to port 3104 and the autocuelog service answers.
- Transport
- TCP · UDP
- Exposure risk
- not rated depends on the program listening
- Encryption
- Unknownnot stated by the registry
- IANA status
- Assigned2 registered services
- Range
- Registered (1024-49151)
- Category
- Other services
Is port 3104 dangerous?
We have no specific security note for port 3104. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 3104
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| autocuelog | 3104 | TCP | Autocue Logger Protocol | - | - |
| autocuetime | 3104 | UDP | Autocue Time Service | - | - |
// source: IANA service name and port number registry
Which program uses port 3104, and is it reachable?
Linux
sudo ss -ltnup 'sport = :3104' # process listening on 3104
sudo lsof -nP -i :3104macOS
sudo lsof -nP -i :3104
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3104 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 3104 netstat -ano | findstr :3104
From another machine
nmap -p 3104 -sV <host> sudo nmap -sU -p 3104 <host> nc -zv <host> 3104
Block it in the firewall
sudo ufw deny 3104/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 3104" -Direction Inbound -LocalPort 3104 -Protocol TCP -Action Block # Windows
What is port 3104 used for?
Port 3104 is assigned by IANA to autocuelog (Autocue Logger Protocol), autocuetime (Autocue Time Service).
Is port 3104 TCP or UDP?
Port 3104 is registered for TCP and UDP.
Is it safe to open port 3104?
It depends on the program that listens on it. Open it only for a service you know and only to the networks that need it. Close the port if nothing on the host needs it.
How do I check if port 3104 is open?
On Linux run "ss -ltnup 'sport = :3104'", on macOS "lsof -nP -i :3104", and on Windows "netstat -ano | findstr :3104" to see the local process. From another machine, "nmap -p 3104 <host>" shows whether it is reachable.