The iSCSI Management API defines a standard interface that applications can use to perform iSCSI management independent of the vendor of the iSCSI HBA. The IMA was designed to be implemented using a combination of a library and plugins. 
An IMA library provides the interface that applications use to perform iSCSI management. Among other things, the library is responsible for loading plugins and dispatching requests from a management application to the appropriate plugin(s).

Plugins are provided by iSCSI HBA vendors to manage their hardware. Typically, a plugin will take a request in the generic format provided by the library and then translate that request into a vendor specific format and forward the request onto the vendor's device driver. In practice, a plugin may use a DLL or shared object library to communicate with the device driver. Also, it may communicate with multiple device drivers. Ultimately, the method a plugin uses to accomplish its work is entirely vendor specific.

IMA v2.0 

SNIA Technical Position

iSCSI Management API (IMA) v2.0

Published

June 30, 2008

IP Disclosures
IMA v1.1

SNIA Technical Position

iSCSI Management API (IMA) v1.1

ANSI Standard

Information Technology - iSCSI Management API Version 1.1.6 (ANSI INCITS 411-2007)
IP Disclosures