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Port 854 (dlep)

IANA assigns port 854 to dlep: Dynamic Link Exchange Protocol (DLEP).

Well-known (system) port, 0-1023 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
dlep TCP Dynamic Link Exchange Protocol (DLEP) IESG RFC 8175
dlep UDP Dynamic Link Exchange Protocol (DLEP) IESG RFC 8175

Registry dates for this port: registered 2017-04-03.

Check what is listening on port 854

Linux: is anything listening on TCP 854?
sudo ss -tlnp 'sport = :854'
Linux: UDP 854
sudo ss -ulnp 'sport = :854'
Linux / macOS: which process owns the port
sudo lsof -nP -i :854
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':854 '
Windows (Command Prompt)
netstat -ano | findstr :854
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 854 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 854
From Windows
Test-NetConnection HOST -Port 854
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 854

Block port 854 in the firewall

ufw
sudo ufw deny 854/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 854 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 854 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 854' -Direction Inbound -Protocol TCP -LocalPort 854 -Action Block
ufw
sudo ufw deny 854/udp
iptables
sudo iptables -A INPUT -p udp --dport 854 -j DROP
nftables
sudo nft add rule inet filter input udp dport 854 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 854' -Direction Inbound -Protocol UDP -LocalPort 854 -Action Block

Related ports

848gdoi853DNS over TLS / DNS over QUIC860iscsi861owamp-control, owamp-test

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