HTTPfy

Port 3878 (fotogcad)

IANA assigns port 3878 to fotogcad: FotoG CAD interface.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
fotogcad TCP FotoG CAD interface Jason Szabo -
fotogcad UDP FotoG CAD interface Jason Szabo -

Registry dates for this port: registered 2003-10.

Check what is listening on port 3878

Linux: is anything listening on TCP 3878?
sudo ss -tlnp 'sport = :3878'
Linux: UDP 3878
sudo ss -ulnp 'sport = :3878'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3878
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3878 '
Windows (Command Prompt)
netstat -ano | findstr :3878
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3878 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3878
From Windows
Test-NetConnection HOST -Port 3878
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3878

Block port 3878 in the firewall

ufw
sudo ufw deny 3878/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3878 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3878 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3878' -Direction Inbound -Protocol TCP -LocalPort 3878 -Action Block
ufw
sudo ufw deny 3878/udp
iptables
sudo iptables -A INPUT -p udp --dport 3878 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3878 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3878' -Direction Inbound -Protocol UDP -LocalPort 3878 -Action Block

Related ports

3876dl-agent, dl_agent3877xmpcr-interface3879appss-lm3880igrs

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