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Port 7550 (cloudsignaling)

IANA assigns port 7550 to cloudsignaling: Cloud Signaling Service.

Registered (user) port, 1024-49151 UDP

Port 7550 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
cloudsignaling UDP Cloud Signaling Service Scott Dawson -

Registry dates for this port: registered 2011-07-01.

Check what is listening on port 7550

Linux: UDP 7550
sudo ss -ulnp 'sport = :7550'
Linux / macOS: which process owns the port
sudo lsof -nP -i :7550
Windows (Command Prompt)
netstat -ano | findstr :7550
Windows (PowerShell)
Get-NetUDPEndpoint -LocalPort 7550

Test it from outside

UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 7550

Block port 7550 in the firewall

ufw
sudo ufw deny 7550/udp
iptables
sudo iptables -A INPUT -p udp --dport 7550 -j DROP
nftables
sudo nft add rule inet filter input udp dport 7550 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 7550' -Direction Inbound -Protocol UDP -LocalPort 7550 -Action Block

Related ports

7548tidp7549nls-tl7551controlone-con7560sncp

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