The UUID component is used as a universally unique identifier
(UUID), which is a 128-bit value (16 bytes). The UUID component
is composed of following unsigned fields:
- time_low: 32-bits (4 bytes). This field is set to a 60-bit timestamp measured in
100-nanosecond units since the date of midnight, October 15, 1582 UTC.
- time_mid: 16-bits (2 bytes). This field is set to a 60-bit timestamp measured in
100-nanosecond units since the date of midnight, October 15, 1582 UTC.
- version: 4-bits -\
- time_hi: 12-bits -/ (2 bytes). This field is set to a 60-bit timestamp measured in
100-nanosecond units since the date of midnight, October 15, 1582 UTC.
- variant: 2-bits -\
- clock_seq: 14-bits -/ (2 bytes). This field is set to a 14-bit random number.
- node: 48-bits (6 bytes)
Note the following when working with the UUID component:
- The variant value is always 2.
- The version must be either 1 (IEEE 802 addres) or 4 (pseudo-random
number).
- The node must be set accordingly.