Host Embedded Controller Interface (HECI ) driver is a software interface that is used to communicate to the AMT subsystem (Management Engine) to access AMT capabilities. Communication between the local host operating system (OS) and the ME is accomplished by means of the HECI driver. HECI is bi-directional, as either the host OS or Intel AMT firmware can initiate transactions.
Local Manageability Service (LMS) is a service that runs locally (in the user space) in the host operating system.LMS exposes AMT functionality through standard interfaces (For Example: general-info interface, firmware update interface, local agent-presence interface, etc.). LMS listens for the request directed to the AMT local host and when a application sends SOAP/HTTP message addressed to the local host then LMS intercepts the request and routes the request to the Management Engine Interface via the HECI driver.
When you have to access any AMT capabilities on the local machine you have to go through the HECI driver to access the Management Engine. LMS is an abstraction that sits on top of the HECI driver (and the ME) that interacts with the ME using standard interfaces.
Let us say you want to read/write data to the third party data store (3PDS) then your application uses the storage library API to accomplish the task. The storage library talks to the LMS interface and that in turn talks to the HECI driver to access the 3PDS. As far as your client application is concerned it typically talks to the LMS or Storage Library (AMT SDK) and eventually the message gets to the ME via the HECI driver.
Please note that currently the HECI driver is available for windows OS and it will be made available on Linux OS in a future release .
The HECI driver and LMS are needed whenever you may need to do anything locally on the AMT machine ( such as storage, agent presence, and general info).
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