According to your version field, you are using version 4 of GUID,
According to rfc 4122.
The algorithm is as follows:
o Set the two most significant bits (bits 6 and 7) of the
clock_seq_hi_and_reserved to zero and one, respectively.
o Set the four most significant bits (bits 12 through 15) of the
time_hi_and_version field to the 4-bit version number from
Section 4.1.3.
o Set all the other bits to randomly (or pseudo-randomly) chosen
values.
This version of GUID does not need to source from timestamp.Timestamp probably isn't good enough if the system is fast. You probably also want jobname, job number, timestamp hashed with some cryptographic function. to generate the final result.
ccw