CyberHunter
// Other services

Port 3611: Six Degrees Port

Port 3611 is assigned by IANA to six-degrees (Six Degrees Port).

3611

How six-degrees works

Other services
client:3611six-degreesresponse client:3611six-degreesresponse

The client sends a request to port 3611 and the six-degrees 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
Registered (1024-49151)
01 Security

Is port 3611 dangerous?

We have no specific security note for port 3611. Its risk depends on the program actually listening on it. General advice for other services services:

  • 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.
02 Registry

IANA registry entries for port 3611

ServicePortTransportDescriptionReferenceUpdated
six-degrees 3611 TCP, UDP Six Degrees Port - 2002-09

// source: IANA service name and port number registry

03 Check it

Which program uses port 3611, and is it reachable?

Linux

sudo ss -ltnup 'sport = :3611'      # process listening on 3611
sudo lsof -nP -i :3611

macOS

sudo lsof -nP -i :3611

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 3611 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 3611
netstat -ano | findstr :3611

From another machine

nmap -p 3611 -sV <host>
sudo nmap -sU -p 3611 <host>
nc -zv <host> 3611

Block it in the firewall

sudo ufw deny 3611/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 3611" -Direction Inbound -LocalPort 3611 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 3611 used for?

Port 3611 is assigned by IANA to six-degrees (Six Degrees Port).

Is port 3611 TCP or UDP?

Port 3611 is registered for TCP and UDP.

Is it safe to open port 3611?

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 3611 is open?

On Linux run "ss -ltnup 'sport = :3611'", on macOS "lsof -nP -i :3611", and on Windows "netstat -ano | findstr :3611" to see the local process. From another machine, "nmap -p 3611 <host>" shows whether it is reachable.

05 Related