User`s guide

Glossary
Agilent VISA User’s Guide 133
commander
In test-system architectures, a device that has the ability to control
another device. In a specialized case, a commander may also be the
device that has sole control over another device (as with the VXI
Commander/Servant hierarchy).
commander session
A session that communicates to the interface’s commander.
Commander sessions are used when an interface is in a
non-Controller role.
communication channel
A communication path between a software element and a resource.
In VISA, “communication channel” is synonymous with “session.”
Every communication channel in VISA is unique.
Connection Expert
An Agilent software utility that helps you quickly establish
connections between your instruments and your PC. It also helps you
troubleshoot connectivity problems. Connection Expert is part of the
Agilent IO Libraries Suite product.
Controller
A device (typically a computer) used to communicate with another
device or devices (typically instruments). The Controller is in charge
of communications and device operation; it controls the flow of
communication and performs addressing and other bus management
functions.
Controller in Charge
The device currently in control of the GPIB.