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Port 3734 (synel-data)

IANA assigns port 3734 to synel-data: Synel Data Collection Port.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
synel-data TCP Synel Data Collection Port David Ashkenazi -
synel-data UDP Synel Data Collection Port David Ashkenazi -

Registry dates for this port: registered 2003-04.

Check what is listening on port 3734

Linux: is anything listening on TCP 3734?
sudo ss -tlnp 'sport = :3734'
Linux: UDP 3734
sudo ss -ulnp 'sport = :3734'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3734
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3734 '
Windows (Command Prompt)
netstat -ano | findstr :3734
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3734 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3734
From Windows
Test-NetConnection HOST -Port 3734
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3734

Block port 3734 in the firewall

ufw
sudo ufw deny 3734/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3734 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3734 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3734' -Direction Inbound -Protocol TCP -LocalPort 3734 -Action Block
ufw
sudo ufw deny 3734/udp
iptables
sudo iptables -A INPUT -p udp --dport 3734 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3734 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3734' -Direction Inbound -Protocol UDP -LocalPort 3734 -Action Block

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3732m-wnn3733multip-msg3735pwdis3736rs-rmi

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