HTTPfy

Port 2043 (isis-bcast)

IANA assigns port 2043 to isis-bcast.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
isis-bcast TCP isis-bcast Ken Chapman -
isis-bcast UDP isis-bcast Ken Chapman -

Check what is listening on port 2043

Linux: is anything listening on TCP 2043?
sudo ss -tlnp 'sport = :2043'
Linux: UDP 2043
sudo ss -ulnp 'sport = :2043'
Linux / macOS: which process owns the port
sudo lsof -nP -i :2043
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':2043 '
Windows (Command Prompt)
netstat -ano | findstr :2043
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 2043 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 2043
From Windows
Test-NetConnection HOST -Port 2043
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 2043

Block port 2043 in the firewall

ufw
sudo ufw deny 2043/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 2043 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 2043 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 2043' -Direction Inbound -Protocol TCP -LocalPort 2043 -Action Block
ufw
sudo ufw deny 2043/udp
iptables
sudo iptables -A INPUT -p udp --dport 2043 -j DROP
nftables
sudo nft add rule inet filter input udp dport 2043 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 2043' -Direction Inbound -Protocol UDP -LocalPort 2043 -Action Block

Related ports

2039prizma2042isis2049NFS2050av-emb-config

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