Directly from e-on's web site:
A Node-Locked License is specific to your computer (it is locked to it during the registration process). Node-Locked Licenses are typically used if you are using xStream Bundle on a single computer. You can also use Node-Locked Licenses for several computers, but each single License will have to be locked to a single computer.

Sounds like activation control to me.  You register each node-locked copy to one specific node (PC).  If you want to install on several PCs, you will need several licensed copies of Vue6 Infinite.