The lobby provider is a client component (DLL) supplied by the developer of a lobby server. It implements communications functions with the lobby server as requested by DirectPlay. A lobby client written using the DirectPlay API can interoperate with any lobby server for which a lobby provider DLL is present on the system.
The DirectX SDK installs a lobby provider for use with the test lobby server (LSERVER.EXE) included with the SDK. This lobby provider is used by the BELLHOP sample lobby client and together they can be used to test the lobby-aware functions your applications.