Intel Management Engine Interface

Built into many Intel chipset based platforms is a small, low power computer subsystem called the Intel Management Engine (intel ME). This technology helps users passively perform various tasks while the system is in sleep, during the boot process and when their systems are running.
It is important that this sub system is functioning correctly to get the most performance and capability from the users computers in an efficient manner.
Intel Management Engine Interface, former HECI (Host Embedded Controller Interface) is a software solution that was designed to communicate with the Intel Active Management Technology (Intel AMT), which is implemented in firmware that is running on the Intel Management Engine. This is the interface between the host and the Intel Management Engine. The interface acts as a PCI device, while the MEI driver handles the communication channel between hosts apps and Intel ME.
The Intel Management Engine supports various management features, which depend on the Intel chipset SKU. Every Intel ME feature is assigned a GUID or UUID and each client is provided with its own protocol, which is message-based and has a header and a payload that goes up to 512 bytes.
A few examples of usage are monitoring hardware state, remote power on and off, OS updates, storage or platform information, hardware KVM, network isolation and IDE device redirection.