This driver, like other NI software and toolkits, is activated with a serial number upon install or first launch. Upon launch, the activation wizard will produce the following prompt, where you can enter the serial number you received upon purchasing NI EtherNet/IP driver.

You can include the EtherNet/IP driver in a LabVIEW installer, if you would like to install it on a second computer running your executable. You do not need any additional license to deploy your executable or installer with Ethernet/IP driver. However, standard Named-User or Computer-Based licensing options applies when using the Ethernet/IP driver in VI format.
An example of how to include NI drivers in your installers is shown in this tutorial of Creating an NI-DAQmx Application Installer.