- Close the port if nothing on the host needs it.
- Identify the process that listens on it (commands below) before opening it in a firewall.
- Expose a service only to the networks that use it.
Port 499: ISO ILL Protocol
Port 499 is assigned by IANA to iso-ill (ISO ILL Protocol).
How iso-ill works
Other servicesThe client sends a request to port 499 and the iso-ill service answers.
- Transport
- TCP · UDP
- Exposure risk
- not rated depends on the program listening
- Encryption
- Unknownnot stated by the registry
- IANA status
- Assigned1 registered service
- Range
- Well-known (0-1023)
- Category
- Other services
Is port 499 dangerous?
We have no specific security note for port 499. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 499
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| iso-ill | 499 | TCP, UDP | ISO ILL Protocol | - | - |
// source: IANA service name and port number registry
Which program uses port 499, and is it reachable?
Linux
sudo ss -ltnup 'sport = :499' # process listening on 499
sudo lsof -nP -i :499macOS
sudo lsof -nP -i :499
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 499 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 499 netstat -ano | findstr :499
From another machine
nmap -p 499 -sV <host> sudo nmap -sU -p 499 <host> nc -zv <host> 499
Block it in the firewall
sudo ufw deny 499/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 499" -Direction Inbound -LocalPort 499 -Protocol TCP -Action Block # Windows
What is port 499 used for?
Port 499 is assigned by IANA to iso-ill (ISO ILL Protocol).
Is port 499 TCP or UDP?
Port 499 is registered for TCP and UDP.
Is it safe to open port 499?
It depends on the program that listens on it. Open it only for a service you know and only to the networks that need it. Close the port if nothing on the host needs it.
How do I check if port 499 is open?
On Linux run "ss -ltnup 'sport = :499'", on macOS "lsof -nP -i :499", and on Windows "netstat -ano | findstr :499" to see the local process. From another machine, "nmap -p 499 <host>" shows whether it is reachable.