Multipoint Attributes in the WSAPROTOCOL_INFOW Structure

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

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

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