HTTPfy

Port 4077 (ascomalarm)

IANA assigns port 4077 to ascomalarm: Ascom IP Alarming.

Registered (user) port, 1024-49151 UDP

Port 4077 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
ascomalarm UDP Ascom IP Alarming Ascom Austria GmbH -

Registry dates for this port: registered 2008-05-01.

Check what is listening on port 4077

Linux: UDP 4077
sudo ss -ulnp 'sport = :4077'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4077
Windows (Command Prompt)
netstat -ano | findstr :4077
Windows (PowerShell)
Get-NetUDPEndpoint -LocalPort 4077

Test it from outside

UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 4077

Block port 4077 in the firewall

ufw
sudo ufw deny 4077/udp
iptables
sudo iptables -A INPUT -p udp --dport 4077 -j DROP
nftables
sudo nft add rule inet filter input udp dport 4077 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 4077' -Direction Inbound -Protocol UDP -LocalPort 4077 -Action Block

Related ports

4075perimlan4076seraph4078cssp4079santools

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