- 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 3420: iFCP User Port
Port 3420 is assigned by IANA to ifcp-port (iFCP User Port).
How ifcp-port works
Other servicesThe client sends a request to port 3420 and the ifcp-port service answers.
- Transport
- TCP · UDP
- Exposure risk
- not rated depends on the program listening
- Encryption
- Unknownnot stated by the registry
- IANA status
- Assigned1 registered service
- Range
- Registered (1024-49151)
- Category
- Other services
Is port 3420 dangerous?
We have no specific security note for port 3420. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 3420
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| ifcp-port | 3420 | TCP, UDP | iFCP User Port | RFC 4172 | - |
// source: IANA service name and port number registry
Which program uses port 3420, and is it reachable?
Linux
sudo ss -ltnup 'sport = :3420' # process listening on 3420
sudo lsof -nP -i :3420macOS
sudo lsof -nP -i :3420
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3420 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 3420 netstat -ano | findstr :3420
From another machine
nmap -p 3420 -sV <host> sudo nmap -sU -p 3420 <host> nc -zv <host> 3420
Block it in the firewall
sudo ufw deny 3420/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 3420" -Direction Inbound -LocalPort 3420 -Protocol TCP -Action Block # Windows
What is port 3420 used for?
Port 3420 is assigned by IANA to ifcp-port (iFCP User Port).
Is port 3420 TCP or UDP?
Port 3420 is registered for TCP and UDP.
Is it safe to open port 3420?
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 3420 is open?
On Linux run "ss -ltnup 'sport = :3420'", on macOS "lsof -nP -i :3420", and on Windows "netstat -ano | findstr :3420" to see the local process. From another machine, "nmap -p 3420 <host>" shows whether it is reachable.