Port 11489 (asgcypresstcps)

IANA assigns port 11489 to asgcypresstcps: ASG Cypress Secure Only.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference

asgcypresstcps TCP ASG Cypress Secure Only David Luxford -

Registry dates for this port: registered 2010-07-01.

Linux: is anything listening on TCP 11489?

sudo ss -tlnp 'sport = :11489'

Linux / macOS: which process owns the port

sudo lsof -nP -i :11489

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':11489 '

Windows (Command Prompt)

netstat -ano | findstr :11489

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 11489 -State Listen | Select LocalAddress,OwningProcess

From another machine

nc -vz -w 5 HOST 11489

From Windows

Test-NetConnection HOST -Port 11489

ufw

sudo ufw deny 11489/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 11489 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 11489 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 11489' -Direction Inbound -Protocol TCP -LocalPort 11489 -Action Block

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Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.