- 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 8711: Nuance Voice Control
Port 8711 is assigned by IANA to nvc (Nuance Voice Control).
8711
How nvc works
Voice & chatPort 8711 sets up the call (who calls whom), then the voice travels as a stream of audio packets.
- Transport
- TCP
- Exposure risk
- not rated depends on the program listening
- Encryption
- Unknownnot stated by the registry
- IANA status
- Assigned1 registered service
- Range
- Registered (1024-49151)
- Category
- Voice & chat
Is port 8711 dangerous?
We have no specific security note for port 8711. Its risk depends on the program actually listening on it. General advice for voice & chat services:
IANA registry entries for port 8711
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| nvc | 8711 | TCP | Nuance Voice Control | - | 2012-10-05 |
| - | 8711 | - | Reserved | - | - |
// source: IANA service name and port number registry
Which program uses port 8711, and is it reachable?
Linux
sudo ss -ltnup 'sport = :8711' # process listening on 8711
sudo lsof -nP -i :8711macOS
sudo lsof -nP -i :8711
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 8711 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 8711 netstat -ano | findstr :8711
From another machine
nmap -p 8711 -sV <host> nc -zv <host> 8711
Block it in the firewall
sudo ufw deny 8711/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 8711" -Direction Inbound -LocalPort 8711 -Protocol TCP -Action Block # Windows
What is port 8711 used for?
Port 8711 is assigned by IANA to nvc (Nuance Voice Control).
Is port 8711 TCP or UDP?
Port 8711 is registered for TCP.
Is it safe to open port 8711?
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 8711 is open?
On Linux run "ss -ltnup 'sport = :8711'", on macOS "lsof -nP -i :8711", and on Windows "netstat -ano | findstr :8711" to see the local process. From another machine, "nmap -p 8711 <host>" shows whether it is reachable.