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Port 3819 (epl-slp)

IANA assigns port 3819 to epl-slp: EPL Sequ Layer Protocol.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
epl-slp TCP EPL Sequ Layer Protocol Hans Weibel -
epl-slp UDP EPL Sequ Layer Protocol Hans Weibel -

Registry dates for this port: registered 2004-10.

Check what is listening on port 3819

Linux: is anything listening on TCP 3819?
sudo ss -tlnp 'sport = :3819'
Linux: UDP 3819
sudo ss -ulnp 'sport = :3819'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3819
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3819 '
Windows (Command Prompt)
netstat -ano | findstr :3819
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3819 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3819
From Windows
Test-NetConnection HOST -Port 3819
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3819

Block port 3819 in the firewall

ufw
sudo ufw deny 3819/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3819 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3819 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3819' -Direction Inbound -Protocol TCP -LocalPort 3819 -Action Block
ufw
sudo ufw deny 3819/udp
iptables
sudo iptables -A INPUT -p udp --dport 3819 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3819 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3819' -Direction Inbound -Protocol UDP -LocalPort 3819 -Action Block

Related ports

3817tapeware3818crinis-hb3820scp3821pmcp

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