[This is preliminary documentation and subject to change.]
The RAS_AUTH_ATTRIBUTE structure is used to pass authentication attributes, of type RAS_AUTH_ATTRIBUTE_TYPE, during an EAP session.
typedef struct _RAS_AUTH_ATTRIBUTE {
    RAS_AUTH_ATTRIBUTE_TYPE raaType;   // attribute type
    DWORD                   dwLength;  // length in bytes of Value
    PVOID                   Value;     // pointer to value or 
                                       // contains value
}RAS_AUTH_ATTRIBUTE, *PRAS_AUTH_ATTRIBUTE;
 Often an array of these structures is used to store or obtain a set of attributes for a given user. Since the number of attributes for a session is unknown, the array must be dynamic. The array is terminated by a structure with an raaType member that has a value of raatMinimum
  Windows NT: Use version 5.0 or later.
  Windows: Unsupported.
  Windows CE: Unsupported.
  Header: Declared in rasauth.h.