I have an X.509 certificate which has the following 2 timestamps:
['validFrom'] = String(13) "120314165227Z"
['validTo'] = String(13) "130314165227Z"
What does the postfix character 'Z' mean. Does it specify the timezone?
This question is related to
timezone
x509certificate
unix-timestamp
timestamp
"Z" doesn't stand for "Zulu"
I don't have any more information than the Wikipedia article cited by the two existing answers, but I believe the interpretation that "Z" stands for "Zulu" is incorrect. UTC time is referred to as "Zulu time" because of the use of Z to identify it, not the other way around. The "Z" seems to have been used to mark the time zone as the "zero zone", in which case "Z" unsurprisingly stands for "zero" (assuming the following information from Wikipedia is accurate):
Around 1950, a letter suffix was added to the zone description, assigning Z to the zero zone, and A–M (except J) to the east and N–Y to the west (J may be assigned to local time in non-nautical applications — zones M and Y have the same clock time but differ by 24 hours: a full day). These can be vocalized using the NATO phonetic alphabet which pronounces the letter Z as Zulu, leading to the use of the term "Zulu Time" for Greenwich Mean Time, or UT1 from January 1, 1972 onward.
The Z stands for 'Zulu' - your times are in UTC. From Wikipedia:
The UTC time zone is sometimes denoted by the letter Z—a reference to the equivalent nautical time zone (GMT), which has been denoted by a Z since about 1950. The letter also refers to the "zone description" of zero hours, which has been used since 1920 (see time zone history). Since the NATO phonetic alphabet and amateur radio word for Z is "Zulu", UTC is sometimes known as Zulu time. This is especially true in aviation, where Zulu is the universal standard.
Source: Stackoverflow.com