- 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 3429: GCSP user port
Port 3429 is assigned by IANA to gcsp (GCSP user port).
How gcsp works
Other servicesThe client sends a request to port 3429 and the gcsp 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 3429 dangerous?
We have no specific security note for port 3429. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 3429
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| gcsp | 3429 | TCP, UDP | GCSP user port | - | 2002-03 |
// source: IANA service name and port number registry
Which program uses port 3429, and is it reachable?
Linux
sudo ss -ltnup 'sport = :3429' # process listening on 3429
sudo lsof -nP -i :3429macOS
sudo lsof -nP -i :3429
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3429 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 3429 netstat -ano | findstr :3429
From another machine
nmap -p 3429 -sV <host> sudo nmap -sU -p 3429 <host> nc -zv <host> 3429
Block it in the firewall
sudo ufw deny 3429/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 3429" -Direction Inbound -LocalPort 3429 -Protocol TCP -Action Block # Windows
What is port 3429 used for?
Port 3429 is assigned by IANA to gcsp (GCSP user port).
Is port 3429 TCP or UDP?
Port 3429 is registered for TCP and UDP.
Is it safe to open port 3429?
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 3429 is open?
On Linux run "ss -ltnup 'sport = :3429'", on macOS "lsof -nP -i :3429", and on Windows "netstat -ano | findstr :3429" to see the local process. From another machine, "nmap -p 3429 <host>" shows whether it is reachable.