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Port 3513 (arcpd)

IANA assigns port 3513 to arcpd: Adaptec Remote Protocol.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
arcpd TCP Adaptec Remote Protocol Hardy Doelfel -
arcpd UDP Adaptec Remote Protocol Hardy Doelfel -

Registry dates for this port: registered 2002-05.

Check what is listening on port 3513

Linux: is anything listening on TCP 3513?
sudo ss -tlnp 'sport = :3513'
Linux: UDP 3513
sudo ss -ulnp 'sport = :3513'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3513
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3513 '
Windows (Command Prompt)
netstat -ano | findstr :3513
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3513 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3513
From Windows
Test-NetConnection HOST -Port 3513
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3513

Block port 3513 in the firewall

ufw
sudo ufw deny 3513/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3513 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3513 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3513' -Direction Inbound -Protocol TCP -LocalPort 3513 -Action Block
ufw
sudo ufw deny 3513/udp
iptables
sudo iptables -A INPUT -p udp --dport 3513 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3513 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3513' -Direction Inbound -Protocol UDP -LocalPort 3513 -Action Block

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