| _PARALLEL_SERVER | Parallel Server structure definition |
| addr_type | Hardware MAC / IP address pair description |
| arp_list_type | Hardware address cache description |
| direntry_type | Embedded File System directory |
| FTP_client_type | Used for information about current FTP connection |
| ftp_return_type | FTP server return structure |
| httpserv_type | Used for information about current connection |
| in_struct | Incoming protocol information |
| SOCKET | Unique description of a bidirectional network communication channel |
| user_type | User authentication and directory specification |
