Multipoint attributes in WSAPROTOCOL_INFOW structure

Three attribute fields are defined in the WSAPROTOCOL_INFOW structure in order to distinguish the different schemes used in the control and data planes respectively:

1. XP1_SUPPORT_MULTIPOINT with a value of 1 indicates this protocol entry supports multipoint communications, and that the following two fields are meaningful.
2. XP1_MULTIPOINT_CONTROL_PLANE indicates whether the control plane is rooted (value = 1) or non-rooted (value = 0).
3. XP1_MULTIPOINT_DATA_PLANE indicates whether the data plane is rooted (value = 1) or non-rooted (value = 0).

Two WSAPROTOCOL_INFOW entries would be present if a multipoint protocol supported both rooted and non-rooted data planes, one entry for each.