typedef struct _LPCP_PORT_OBJECT
{
     PLPCP_PORT_OBJECT ConnectionPort;
     PLPCP_PORT_OBJECT ConnectedPort;
     LPCP_PORT_QUEUE MsgQueue;
     CLIENT_ID Creator;
     PVOID ClientSectionBase;
     PVOID ServerSectionBase;
     PVOID PortContext;
     PETHREAD ClientThread;
     SECURITY_QUALITY_OF_SERVICE SecurityQos;
     SECURITY_CLIENT_CONTEXT StaticSecurity;
     LIST_ENTRY LpcReplyChainHead;
     LIST_ENTRY LpcDataInfoChainHead;
     union
     {
          PEPROCESS ServerProcess;
          PEPROCESS MappingProcess;
     };
     WORD MaxMessageLength;
     WORD MaxConnectionInfoLength;
     ULONG Flags;
     KEVENT WaitEvent;
} LPCP_PORT_OBJECT, *PLPCP_PORT_OBJECT;

Windows Vista Kernel Structures