With the exception of a repeater (a repeater is programmatically invisible; it has no attributes), all IBA devices contain a series of attributes that various managers perform operations upon (e.g., reads or writes) for various reasons. For example:
To discover the existence of an IBA device.
To discover the IBA device type (e.g., a CA, a switch, or a router).
To ascertain the device's current status.
To determine the number of ports implemented on the device.
To control the device's operational characteristics.
etc.