Usage of Skype on the Missouri S&T Network

Skype is a peer-to-peer application for making phone calls using a computer. Although Skype is not normally a problem, the protocol is similar to peer-to-peer file sharing protocols and under certain circumstances can put an excessive load on the network infrastructure. When these circumstances occur, your Skype session becomes a supernode.

Preventing Skype from running as a supernode has no impact on using it, but it does reduce the load on the system and network. For these reasons it is strongly recommended to prevent Skype from becoming a supernode. To do so you must be running Skype 3.0 or newer and modify the registry. Once the change has been made the Skype service must be restarted, this happens each time the computer is rebooted.

How to prevent Skype from becoming a supernode:


  1. Right-click the security update download: SkypeNoNode
  2. Save the file as SkypeNoNode.reg to your desktop.
  3. Double-click the file SkypeNoNode.reg and click run.
  4. When asked if you want to add the information to the registry, click yes.*

* If an "error accessing the registry" comes up you may not have permissions to access. Contact the IT Help Desk at  573-341-4357 (HELP).


  1. Open System Preference
  2. Click Security & Privacy
  3. Click Firewall tab
  4. Click Advanced
  5. Click Skype
  6. Select Block incoming connections
  7. Click Ok

This will prevent Skype from becoming a supernode, and you will still be able to receive incoming calls.