The Network Time Protocol (NTP) uses a 64-bit timestamp consisting of a 32-bit part for seconds and a 32-bit part for fractional seconds. The NTP epoch began on January 1, 1900 (00:00:00 UTC). Because the 32-bit seconds field will overflow in 2036 (known as the Year 2036 problem), NTPv4 introduced mechanisms to handle different 'Eras', but standard timestamp values count seconds from exactly 1900-01-01T00:00:00Z. For instance, UNIX epoch starts 70 years after NTP epoch.