EEM is part of the USB CDC specification, but unlike ECM, the EEM specification lacks the control requests to extend the Ethernet interface over USB. Instead, EEM utilizes the USB bandwidth to move Ethernet packets between a device and a host (While ECM will simply act as a channel for transmitting Ethernet Packets over a USB Bus to the device which will then export them to the network, the EEM can encapsulate several Ethernet frames into a single USB packet and by thus utilize the USB bandwidth to achieve maximal transfer performance).
A general use case of a CDC EEM device would be creating "Network over USB" connectivity with a host, without extending the EEM device to serve as a "NIC" to an actual LAN/WLAN.
DriverCore CDC EEM supports USB device bridging and bandwidth optimization by specific EEM USB packet payloads. Because EEM does extend any Ethernet control packets beyond the USB driver layer, it is not designed for LAN/WLAN types of devices.
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- Multiple USB CDC EEM devices on separate physical USB devices
- USB device bridging
- Device management control requests
- Composite USB devices with multiple CDC EEM functions
- Getting/setting NDIS Object Identifiers (OID's)
- NDIS 5.0/5.1 and NDIS 6.0