HTTPfy

Port 4455 (prchat-user)

IANA assigns port 4455 to prchat-user: PR Chat User.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
prchat-user TCP PR Chat User - -
prchat-user UDP PR Chat User - -

Check what is listening on port 4455

Linux: is anything listening on TCP 4455?
sudo ss -tlnp 'sport = :4455'
Linux: UDP 4455
sudo ss -ulnp 'sport = :4455'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4455
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':4455 '
Windows (Command Prompt)
netstat -ano | findstr :4455
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4455 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 4455
From Windows
Test-NetConnection HOST -Port 4455
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 4455

Block port 4455 in the firewall

ufw
sudo ufw deny 4455/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 4455 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 4455 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 4455' -Direction Inbound -Protocol TCP -LocalPort 4455 -Action Block
ufw
sudo ufw deny 4455/udp
iptables
sudo iptables -A INPUT -p udp --dport 4455 -j DROP
nftables
sudo nft add rule inet filter input udp dport 4455 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 4455' -Direction Inbound -Protocol UDP -LocalPort 4455 -Action Block

Related ports

4453nssalertmgr4454nssagentmgr4456prchat-server4457prRegister

All port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.