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Port 3845 (v-one-spp)

IANA assigns port 3845 to v-one-spp: V-ONE Single Port Proxy.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
v-one-spp TCP V-ONE Single Port Proxy Daniel Becker 3 -
v-one-spp UDP V-ONE Single Port Proxy Daniel Becker 3 -

Check what is listening on port 3845

Linux: is anything listening on TCP 3845?
sudo ss -tlnp 'sport = :3845'
Linux: UDP 3845
sudo ss -ulnp 'sport = :3845'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3845
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3845 '
Windows (Command Prompt)
netstat -ano | findstr :3845
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3845 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3845
From Windows
Test-NetConnection HOST -Port 3845
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3845

Block port 3845 in the firewall

ufw
sudo ufw deny 3845/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3845 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3845 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3845' -Direction Inbound -Protocol TCP -LocalPort 3845 -Action Block
ufw
sudo ufw deny 3845/udp
iptables
sudo iptables -A INPUT -p udp --dport 3845 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3845 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3845' -Direction Inbound -Protocol UDP -LocalPort 3845 -Action Block

Related ports

3843quest-agent3844rnm3846an-pcp3847msfw-control

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