Customer Service Center

Generally speaking, this is the explanation for each:
 

Spirent TestCenter LabServer (a.k.a “Spirent vLS” or "LS") is a virtual machine deployed with off-the-shelf hypervisors that provide the solution that eliminates the need for a dedicated test management console computer and supports team collaboration during testing. With this solution, the test logic moves from the local PC to the Virtual LabServer virtual machine. This LabServer is managed through the Spirent application called “Session Manager”

The lab server helps in maintaining the session to the Spirent Test Center chassis. The Spirent TestCenter LS appliance is the Spirent TestCenter server. Together, Spirent TestCenter Session Manager and Spirent TestCenter LabServer provide the solution that eliminates the need for a dedicated test management console computer and supports team collaboration during testing. Working through the Lab Server provides mobility to the user since the user initiates the test session from his laptop through the lab server to the STC chassis rather than initiating it directly to the chassis.

This is a graphical representation:



                You can refer to:

•    DATASHEET - Spirent Virtual Lab Server :  https://www.spirent.com/assets/u/spirent_virtual_labserver_datasheet
 

Spirent Virtual License Server (a.k.a “Virtual Controller”) is also a virtual machine that basically manages/control licenses. The license server is only required if you are using a virtual chassis and it is optional for physical chassis. So, on this VM you install the licenses that serves the virtual ports licenses, hence through the normal GUI the virtual ports would check for licenses needed in bulk through a connection with the License Server.

                You can refer to:

•    DOC10586 - Spirent Virtual Controller – VM (USB Dongle or UUID version) Quick Start Guide
 

Spirent TestCenter (BLL) Virtual Licensing with AION has been introduced starting in the 5.18 Spirent TestCenter release, and it is a License Server service available through Spirent AION (Spirent AION is a new central management hub for Network and Cloud testing using Spirent TestCenter Hardware, Virtual and CloudSure solutions)
 

You can refer to:
•    DOC12187 - Spirent TestCenter with Spirent AION Licensing Quick Start Guide
•    Spirent AION web page
•    TRN11202 - ---Essentials of Spirent AION---