1.8 Vendor-Extensible Fields
This protocol can be transmitted over network protocols other than the IP networking stack. The protocol includes a Service Provider Data field in the DPLAYI_PACKEDPLAYER structure (section 2.2.2) and the DPLAYI_SUPERPACKEDPLAYER structure (section 2.2.3) that can be used to transmit protocol-specific information.
Each game can also extend the protocol with player, per-group, and per-game-session data. The per-player and per-group data is specified in the Player Data field of the DPLAYI_PACKEDPLAYER structure (section 2.2.2) and the DPLAYI_SUPERPACKEDPLAYER structure (section 2.2.3). The per-game-session data is contained in the Application Defined 1 and Application Defined 4 fields of the DPSESSIONDESC2 structure (section 2.2.5).
This protocol uses HRESULT values as defined in [MS-ERREF] section 2.1. Vendors can define their own HRESULT values provided that they set the C bit (0x20000000) for each vendor-defined value to indicate that the value is a customer code.