ICC Help: timestamp
ICC has developed a system that eliminates the effects that lag has on your clock in ICC games. A "TimeStamp" program measures the amount of time you spend thinking about each move. The ICC server uses this information to update the clocks.
In most games, the full amount of the delay in transmission (lag) will be credited back to the clock, and only the time the player spent on the move will actually be deducted from their clock. When the server is updated with information about the actual time used for a move, the lag time being credited may result in the appearance of the time being added to your opponent’s clock. In fact, the time added was never used by your opponent, but was instead the time it took for your last move and your opponent’s last move to travel between the ICC server and your respective computers.
In rating pool games and in some special prize tournaments, the Flexible Lag Compensation system limits how much lag time a player will be compensated for during games. In such games a player will be compensated for up to one second (1000 milliseconds) of lag per move. If the player’s lag is less than one second, as it is for 98% or 99% of players, none of the lag will be charged to their clock. If lag exceeds one second during any move, the first second of lag time is "free" and any additional lag time will be charged to the player’s clock. See help LagCompensation.
Timestamp is built into the interfaces ICC for Windows, ICC for Mac, Dasher, BlitzIn, Lantern, Jin, Fixation, etc. And it will run automatically with WinBoard and some other interfaces. So normally, you don't need to do anything special to use timestamp.
For some other interfaces, you run timestamp in addition to your usual ICC interface program. It has been tested with xboard, xics, ziics, and giics, slics, MacICS, and other interfaces. There are two main versions of timestamp: Unix timestamp and MS Windows timestamp.
Unix timestamp works with any client if you connect to ICC through a Unix machine. Of course it works if your own machine runs Unix. It also works if your own machine does not run Unix, but you connect to ICC through a shell account on a Unix machine. In the latter case, though, timestamp cannot compensate for any lag that might exist between your own machine and the Unix machine where you run timestamp. Such lag can occur (for example) if the Unix machine is heavily loaded, so that you are not getting enough CPU time, or if you are calling over a noisy phone line with an error-correcting modem.
You can use MS Windows timestamp if you have a PC running Microsoft Windows that is on the Internet, and your Internet software package supports the 32-bit Winsock API (which it should). Only very old Windows 3.1 machines or versions of AOL from about 1995 are likely to have a problem.
All data sent in both directions between the timestamp program and the ICC server is encrypted.