HTTPfy

Port 3073 (vcrp)

IANA assigns port 3073 to vcrp: Very simple chatroom prot.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
vcrp TCP Very simple chatroom prot Andreas Wurf -
vcrp UDP Very simple chatroom prot Andreas Wurf -

Check what is listening on port 3073

Linux: is anything listening on TCP 3073?
sudo ss -tlnp 'sport = :3073'
Linux: UDP 3073
sudo ss -ulnp 'sport = :3073'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3073
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3073 '
Windows (Command Prompt)
netstat -ano | findstr :3073
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3073 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3073
From Windows
Test-NetConnection HOST -Port 3073
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3073

Block port 3073 in the firewall

ufw
sudo ufw deny 3073/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3073 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3073 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3073' -Direction Inbound -Protocol TCP -LocalPort 3073 -Action Block
ufw
sudo ufw deny 3073/udp
iptables
sudo iptables -A INPUT -p udp --dport 3073 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3073 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3073' -Direction Inbound -Protocol UDP -LocalPort 3073 -Action Block

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3071xplat-replicate3072csd-monitor3074Xbox network / Call of Duty3075orbix-locator

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