Windows CE provides data-link layer support for serial I/O and local area networks (LANs). Low-level software, called device drivers, operate at the data-link layer, managing communication with physical layer hardware. For example, the serial driver manages the serial port, and the Microsoft Network Driver Interface Specification (NDIS) drivers manage network interface connections.
The Windows CE NDIS is a subset of Microsoft NDIS version 4.0, which is used in Windows–based operating systems. Windows CE supports NDIS Ethernet (802.3) miniport drivers. Windows CE also supports Serial Infrared (SIR) and Fast Infrared (FIR) IrDA miniport drivers. For more information on NDIS architecture and network connectivity issues, see the Microsoft Windows CE Device Driver Kit.
Operating at the data-link layer, or between the data-link layer and the network layer, are the Microsoft Telephony API (TAPI), Unimodem and the point-to-point protocol (PPP) and Serial Line Internet Protocol (SLIP) for direct serial and dial-up connections. For more information on TAPI and Unimodem, see Telephony API. For more information on PPP and SLIP, see Serial Communications and Remote Access Service.