3.4 Minimum Binding Requirements

The developer of a network driver must at a minimum ensure that the following required net rules, and possibly some optional rules, are written into the registry by the driver’s setup file.

When system setup runs a network driver’s .inf script, this file writes that driver's net rules as value entries in the registry at HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NameOfComponent
\CurrentVersion\NetRules. The following list summarizes the predefined names of possible value entries in the NetRules key and whether each is required or optional:

• type - required

• use - optional

  A use value is optional in the sense that no error messages will be generated if it is not defined in a component’s .inf file. However, if it is undefined, NCPA assumes that the use value for this component is defined as a Service. Therefore, as a practical matter, a use value entry is required for every transport, intermediate driver, and NIC driver.

• bindform - required

• class - optional

  This entry is not required unless the driver is defining a subclass of either of the predefined classes, ndisDriver or Transport.

• bindable - optional

  This entry is used to limit the underlying devices to which a particular component will bind itself. NIC drivers provide a bindable value in the driver .inf file to specify that they bind only to specific types of adapters.

  Transport protocols generally do not provide a bindable value.

The registry must also contain the following net rules for each adapter in the system:

• type

• bindform

• class

The setup file for any driver that manages an adapter writes the net rules for that adapter into the registry HKEY_LOCAL\SOFTWARE\Microsoft\WindowsNT
\CurrentVersion\NetworkCards\CardNumber\NetRules key. It is unnecessary to write a use net rule value for an adapter. Because the net rules for an adapter are written under the preceding key, adapter is assumed to be the value of use.

Information about the syntax for each of the preceding value entries follows.