NetworkAddress Parameter Not Supported for a Modem

CAUSE

There are two reasons why assigning a specific media access control address is not supported. The first reason is that a modem uses Serial.sys, and serial is not a device that NetworkAddress is relative to. The second reason is that the NetworkAddress registry override parameter is an optional value that is enforced only for Token Ring. So, if Serial.sys supported the NetworkAddress parameter, assigning a specific media access control address could be done. However, this would get more complicated with multiple serial devices in a machine. So, although a modem is a WAN device, it does not use a network device driver, which is where the optional NetworkAddress registry override parameter would be managed.