Source: ​bimmerscan

Over the years BMW has used a number of different diagnostic hardware, here’s a look of current and previous hardware.
ICOM (Integration Communication Optical Module) – 3rd generation vehicle interface used by BMW dealers. It supports ADS, CAN, MOST and Ethernet communication to the vehicle and is compatible with BMW Standard Tools, E-Sys and ISTA. It’s composed of three parts (for cars)
ICOM A – Main piece and connects to the network and to the OBD port on the car
ICOM A2 – *** NEW *** ICOM A2 is a direct replacement for the ICOM A, it works exactly the same as the ICOM A and was released to overcome some of the design issues BMW felt existed with the ICOM A. It has a significantly more powerful processor, more storage capacity and a robust aluminum case will help to avoid damage when using in harsh environments.