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Port 3243 (timelot)

IANA assigns port 3243 to timelot: Timelot Port.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
timelot TCP Timelot Port David Ferguson -
timelot UDP Timelot Port David Ferguson -

Registry dates for this port: registered 2002-02.

Check what is listening on port 3243

Linux: is anything listening on TCP 3243?
sudo ss -tlnp 'sport = :3243'
Linux: UDP 3243
sudo ss -ulnp 'sport = :3243'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3243
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3243 '
Windows (Command Prompt)
netstat -ano | findstr :3243
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3243 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3243
From Windows
Test-NetConnection HOST -Port 3243
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3243

Block port 3243 in the firewall

ufw
sudo ufw deny 3243/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3243 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3243 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3243' -Direction Inbound -Protocol TCP -LocalPort 3243 -Action Block
ufw
sudo ufw deny 3243/udp
iptables
sudo iptables -A INPUT -p udp --dport 3243 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3243 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3243' -Direction Inbound -Protocol UDP -LocalPort 3243 -Action Block

Related ports

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