- Use strong credentials and TLS for signalling.
- Rate-limit registrations to stop extension scanning and toll fraud.
- Alert on unexpected chat protocols leaving servers (possible command and control).
Port 6697: Internet Relay Chat via TLS/SSL
Port 6697 is assigned by IANA to ircs-u (Internet Relay Chat via TLS/SSL).
6697
How ircs-u works
Voice & chatPort 6697 sets up the call (who calls whom), then the voice travels as a stream of audio packets. Everything is encrypted: someone on the path only sees unreadable bytes.
- Transport
- TCP
- Exposure risk
- not rated depends on the program listening
- Encryption
- EncryptedTLS or built-in crypto
- IANA status
- Assigned1 registered service
- Range
- Registered (1024-49151)
- Category
- Voice & chat
Is port 6697 dangerous?
We have no specific security note for port 6697. Its risk depends on the program actually listening on it. General advice for voice & chat services:
IANA registry entries for port 6697
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| ircs-u | 6697 | TCP | Internet Relay Chat via TLS/SSL | RFC 7194 | 2014-02-11 |
| - | 6697 | - | Reserved | - | - |
// source: IANA service name and port number registry
Which program uses port 6697, and is it reachable?
Linux
sudo ss -ltnup 'sport = :6697' # process listening on 6697
sudo lsof -nP -i :6697macOS
sudo lsof -nP -i :6697
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 6697 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 6697 netstat -ano | findstr :6697
From another machine
nmap -p 6697 -sV <host> nc -zv <host> 6697
Block it in the firewall
sudo ufw deny 6697/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 6697" -Direction Inbound -LocalPort 6697 -Protocol TCP -Action Block # Windows
What is port 6697 used for?
Port 6697 is assigned by IANA to ircs-u (Internet Relay Chat via TLS/SSL).
Is port 6697 TCP or UDP?
Port 6697 is registered for TCP.
Is it safe to open port 6697?
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. Use strong credentials and TLS for signalling.
How do I check if port 6697 is open?
On Linux run "ss -ltnup 'sport = :6697'", on macOS "lsof -nP -i :6697", and on Windows "netstat -ano | findstr :6697" to see the local process. From another machine, "nmap -p 6697 <host>" shows whether it is reachable.