Articles in The '__utma-cookie' Tag

What are we going to do at 3:14:07 UTC, January 19, 2038?

by MoreVisibility

Start the countdown right now! In a little under 29 years from now in the year 2038, Web Analytics engineers at Google, Yahoo, Omniture, Coremetrics, and WebTrends will have some very tough choices to make – and it’s never too early to start thinking about them!

This isn’t a trivial issue like Y2K or something like the digital TV transition day on June 12th of this year – no, no, no! This has the potential to seriously compromise cookie integrity, and potentially “break” visitor tracking, industry-wide!

What is happening in 2038?

On Tuesday, January 19th at exactly 3:14:07 UTC, all computer software programs (including Web Analytics Cookies) that store system time as a signed 32-bit integer (like a Unix timestamp) will start to “wrap around”, storing time as a negative number, causing every system using signed 32-bit integers to interpret time as 1901, and not 2038.

Whoa, Whoa! Back Up – I have no clue what you’re talking about.

Okay, let me try to break this down for you. Almost every 20th century computer uses a signed 32-bit integer which keeps track of system time on your computer, on servers, ATM machines, iPods and iPhones, and so on. This “signed 32-bit integer” business is also known by another name – Unix Time (or also “POSIX” time). This time is represented by the number of seconds since January 1, 1970.

If you take a look at your browser’s cookies, you’ll see endless strings of numbers and dots, like this:

The cookie selected here in this image is the __utma cookie from Google Analytics, and the 10-digit number that I have highlighted represents the first time I visited the Google.com website. This number – 1239628694 – is a Unix Timestamp, and when you do the math (or use a conversion tool somewhere online), this number translates to Mon, 13 Apr 2009 13:18:14 GMT (of course, I most likely cleared my cookies – yes World, I clear cookies from my computer, too!)

So what’s the problem again?

Okay – the problem with this comes due to the way modern computer programs calculate this 10-digit number. That’s what you need to know (Warning: This next party is very geeky). They almost all use a very standard 4-byte integer to count up the seconds, which is 31 bits long, able to contain a maximum value of 2 to the power of 31. The 32nd bit is the sign, which of course is positive (+). When you do the math, the maximum number that computer software programs can reach and stay positive is 2147483646. When you add one more second to it – 2147483647 – the positive sign will become a negative sign, and instead of Tuesday, 3:14:07 on January 19, 2038, computers everywhere will display the time as Friday, 8:45:52 on December 13, 1901.

Can’t this be fixed? Can’t we just ignore the date and move on?

Unfortunately, it’s not that simple. Most every operating system stores system time as a 32-bit integer, and system time is a very big component of a functioning software program (they absolutely need to be able to come up with a positive time stamp). So, it’s not an easy fix – most likely, entire software programs will need to be re-written and re-programmed to avoid Y2038K.

This includes personal computer operating systems, ATM machine software, other electronic devices with computer-like components, and, yes, Web Analytics cookies.

Okay – Y2038K? Give me a break – this is TWENTY-NINE and a HALF years away! I think you’re jumping the gun here.

You’ll be surprised how fast 29 and a half years goes by in computer programming. Think of this – we’re in the year 2009, and we’re using a timestamp that starts counting seconds from 1970 (39 Years Ago), which was first published in 1988 (21 Years Ago). Most of us are still using Office 2003 (6 Years Ago).

29 Years is right around the corner – so I hope that we can come up with some kind of conversion tool, some type of new timestamp calculation, some new 64-bit integer system that can seamlessly transition all software programs and Web Analytics Cookie Timestamps for the next generation!

*Note: Some of this blog post is obviously “tongue and cheek”. I am not really sounding the general alarm about what will happen in 2038 – but hey, it’s never too early to start planning for the future! :)”