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Port 19788 (mle)

IANA assigns port 19788 to mle: Mesh Link Establishment.

Registered (user) port, 1024-49151 UDP

Port 19788 is normally used over UDP; the checker tests TCP only, so a "filtered" result does not mean the UDP service is down.

IANA assignment

Service nameProtoDescriptionAssigneeReference
mle UDP Mesh Link Establishment IESG -

Registry dates for this port: registered 2012-12-18.

Check what is listening on port 19788

Linux: UDP 19788
sudo ss -ulnp 'sport = :19788'
Linux / macOS: which process owns the port
sudo lsof -nP -i :19788
Windows (Command Prompt)
netstat -ano | findstr :19788
Windows (PowerShell)
Get-NetUDPEndpoint -LocalPort 19788

Test it from outside

UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 19788

Block port 19788 in the firewall

ufw
sudo ufw deny 19788/udp
iptables
sudo iptables -A INPUT -p udp --dport 19788 -j DROP
nftables
sudo nft add rule inet filter input udp dport 19788 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 19788' -Direction Inbound -Protocol UDP -LocalPort 19788 -Action Block

Related ports

19540sxuptp19541jcp19790faircom-db19998iec-104-sec

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