Because Internet Protocol (IP) is so prevalent, Microsoft will provide direct IP address resolution to ATM, doing away with the need for IP to first be translated through a LAN Emulation module.
For TCP/IP, the ATM Forum defined a special module, called "Classical IP over ATM," which is an Address Resolution Protocol (ARP) module. Defined in Internet RFC 1577, this ATM ARP will be included in future Windows 95 and Windows NT operating systems.
Microsoft's implementation will allow IP to work through either LAN Emulation or ATM ARP. This preserves connectivity with non-Windows systems that might implement only LAN Emulation or ATM ARP, but not both. Although ATM ARP will provide the most efficient transport, LAN Emulation is also required for NetBEUI, IPX, and similar protocols. And so the Windows implementation will allow either path.