HTTPfy

Port 3523 (odeumservlink)

IANA assigns port 3523 to odeumservlink: Odeum Serverlink.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
odeumservlink TCP Odeum Serverlink Mads Peter Back -
odeumservlink UDP Odeum Serverlink Mads Peter Back -

Registry dates for this port: registered 2002-06.

Check what is listening on port 3523

Linux: is anything listening on TCP 3523?
sudo ss -tlnp 'sport = :3523'
Linux: UDP 3523
sudo ss -ulnp 'sport = :3523'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3523
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3523 '
Windows (Command Prompt)
netstat -ano | findstr :3523
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3523 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3523
From Windows
Test-NetConnection HOST -Port 3523
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3523

Block port 3523 in the firewall

ufw
sudo ufw deny 3523/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3523 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3523 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3523' -Direction Inbound -Protocol TCP -LocalPort 3523 -Action Block
ufw
sudo ufw deny 3523/udp
iptables
sudo iptables -A INPUT -p udp --dport 3523 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3523 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3523' -Direction Inbound -Protocol UDP -LocalPort 3523 -Action Block

Related ports

3521mc3ss3522nssocketport3524ecmport3525eisport

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