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Port 4113 (aipn-reg)

IANA assigns port 4113 to aipn-reg: AIPN LS Registration.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
aipn-reg TCP AIPN LS Registration Qiang Zhang 2 -
aipn-reg UDP AIPN LS Registration Qiang Zhang 2 -

Registry dates for this port: registered 2006-10.

Check what is listening on port 4113

Linux: is anything listening on TCP 4113?
sudo ss -tlnp 'sport = :4113'
Linux: UDP 4113
sudo ss -ulnp 'sport = :4113'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4113
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':4113 '
Windows (Command Prompt)
netstat -ano | findstr :4113
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4113 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 4113
From Windows
Test-NetConnection HOST -Port 4113
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 4113

Block port 4113 in the firewall

ufw
sudo ufw deny 4113/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 4113 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 4113 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 4113' -Direction Inbound -Protocol TCP -LocalPort 4113 -Action Block
ufw
sudo ufw deny 4113/udp
iptables
sudo iptables -A INPUT -p udp --dport 4113 -j DROP
nftables
sudo nft add rule inet filter input udp dport 4113 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 4113' -Direction Inbound -Protocol UDP -LocalPort 4113 -Action Block

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Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.