CyberHunter
// Media & streaming

Port 651: IEEE MMS

Port 651 is assigned by IANA to ieee-mms (IEEE MMS).

651

How ieee-mms works

Media & streaming
playercameraieee-mms playercameraieee-mms

The device streams video frames over port 651, continuously, as they are captured.

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)
01 Security

Is port 651 dangerous?

We have no specific security note for port 651. Its risk depends on the program actually listening on it. General advice for media & streaming services:

  • Require authentication on cameras and media servers.
  • Keep IP cameras and recorders off the Internet; use a VPN for remote viewing.
  • Update device firmware.
02 Registry

IANA registry entries for port 651

ServicePortTransportDescriptionReferenceUpdated
ieee-mms 651 TCP, UDP IEEE MMS - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 651, and is it reachable?

Linux

sudo ss -ltnup 'sport = :651'      # process listening on 651
sudo lsof -nP -i :651

macOS

sudo lsof -nP -i :651

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 651 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 651
netstat -ano | findstr :651

From another machine

nmap -p 651 -sV <host>
sudo nmap -sU -p 651 <host>
nc -zv <host> 651

Block it in the firewall

sudo ufw deny 651/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 651" -Direction Inbound -LocalPort 651 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 651 used for?

Port 651 is assigned by IANA to ieee-mms (IEEE MMS).

Is port 651 TCP or UDP?

Port 651 is registered for TCP and UDP.

Is it safe to open port 651?

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. Require authentication on cameras and media servers.

How do I check if port 651 is open?

On Linux run "ss -ltnup 'sport = :651'", on macOS "lsof -nP -i :651", and on Windows "netstat -ano | findstr :651" to see the local process. From another machine, "nmap -p 651 <host>" shows whether it is reachable.

05 Related