Universidad de Buenos Aires Universidad de Buenos Aires Universidad de Buenos Aires Deutsche Telekom Synchronizing Internet Clock Frequency specifies a new secure method to synchronize difference clocks on the Internet, assuring smoothness (i.e., frequency stability) and robustness to man-in-the-middle attacks. In 90% of all cases, Synchronized Internet Clock Frequency is highly accurate, with a Maximum Time Interval Error less than 25 microseconds by a minute. Synchronized Internet Clock Frequency is based on a regular packet exchange and works with commodity terminal hardware.