SIXNET stations log time stamped data and store it in data files. These files sooner or later need to be transferred to a central server where they can be archived and viewed. There are two basic methods for accomplishing this data transfer:
Host Transfer - The host computer can poll for the logged data. In this scenario, each station is a slave, responding to external information requests. Historically, this is the classic way data exchanges have been performed.
Client Transfer - Each station, acting as the master or "client", sends its information to the server automatically. There are many advantages to this client transfer method, especially when the Internet is used to transfer data. In Windows based systems the optional Datalog Server software acts as a receiver of this client initiated data transfer.
When a station transmits data to the server, the optional Datalog Server receives and acknowledges the messages and optionally synchronizes the station’s clock with the server’s time of day clock. The received data is stored in ASCII database files that may be viewed with Excel or any other suitable database / spreadsheet program. Data from each station is stored in its own file and a feature is provided in the server configuration to automatically organize the files by day, week or month.
The Datalog Server will accept data from multiple serial ports and/or the Ethernet port simultaneously and is suitable for large systems with many stations. This server is supplied as part of the optional Datalogging feature set of the SIXNET I/O Tool Kit.
See Also: Client Initiated Data Transfers