CyberHunter
// Voice & chat

Port 22555: Vocaltec Internet Phone

Port 22555 is assigned by IANA to vocaltec-phone (Vocaltec Internet Phone), vocaltec-wconf (Vocaltec Web Conference).

22555

How vocaltec-phone works

Voice & chat
callercalleevocaltec-phone callercalleevocaltec-phone

Port 22555 sets up the call (who calls whom), then the voice travels as a stream of audio packets.

Transport
UDP · TCP
Exposure risk
not rated depends on the program listening
Encryption
Unknownnot stated by the registry
IANA status
Assigned2 registered services
Range
Registered (1024-49151)
Category
Voice & chat
01 Security

Is port 22555 dangerous?

We have no specific security note for port 22555. Its risk depends on the program actually listening on it. General advice for voice & chat services:

  • 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).
02 Registry

IANA registry entries for port 22555

ServicePortTransportDescriptionReferenceUpdated
vocaltec-phone 22555 UDP Vocaltec Internet Phone - -
vocaltec-wconf 22555 TCP Vocaltec Web Conference - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 22555, and is it reachable?

Linux

sudo ss -ltnup 'sport = :22555'      # process listening on 22555
sudo lsof -nP -i :22555

macOS

sudo lsof -nP -i :22555

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 22555 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 22555
netstat -ano | findstr :22555

From another machine

nmap -p 22555 -sV <host>
sudo nmap -sU -p 22555 <host>
nc -zv <host> 22555

Block it in the firewall

sudo ufw deny 22555/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 22555" -Direction Inbound -LocalPort 22555 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 22555 used for?

Port 22555 is assigned by IANA to vocaltec-phone (Vocaltec Internet Phone), vocaltec-wconf (Vocaltec Web Conference).

Is port 22555 TCP or UDP?

Port 22555 is registered for UDP and TCP.

Is it safe to open port 22555?

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 22555 is open?

On Linux run "ss -ltnup 'sport = :22555'", on macOS "lsof -nP -i :22555", and on Windows "netstat -ano | findstr :22555" to see the local process. From another machine, "nmap -p 22555 <host>" shows whether it is reachable.

05 Related