Port 4894 (lyskom)

IANA assigns port 4894 to lyskom: LysKOM Protocol A.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference

lyskom TCP LysKOM Protocol A Per Cederqvist -

lyskom UDP LysKOM Protocol A Per Cederqvist -

Linux: is anything listening on TCP 4894?

sudo ss -tlnp 'sport = :4894'

Linux: UDP 4894

sudo ss -ulnp 'sport = :4894'

Linux / macOS: which process owns the port

sudo lsof -nP -i :4894

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':4894 '

Windows (Command Prompt)

netstat -ano | findstr :4894

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 4894 -State Listen | Select LocalAddress,OwningProcess

From another machine

nc -vz -w 5 HOST 4894

From Windows

Test-NetConnection HOST -Port 4894

UDP probe (no reply does not prove it is closed)

nc -vzu -w 5 HOST 4894

ufw

sudo ufw deny 4894/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 4894 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 4894 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 4894' -Direction Inbound -Protocol TCP -LocalPort 4894 -Action Block

ufw

sudo ufw deny 4894/udp

iptables

sudo iptables -A INPUT -p udp --dport 4894 -j DROP

nftables

sudo nft add rule inet filter input udp dport 4894 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block UDP 4894' -Direction Inbound -Protocol UDP -LocalPort 4894 -Action Block

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