When building a network, you will shop around and compare plenty of models for each piece of hardware that you need. Sometimes, it’s hard to keep track of everything and know what items are new and which have been around for a while.
If you’re investing in Cisco products, then there’s actually a mechanism in place that can help you know exactly when a device was manufactured. Below, you’ll see a complete guide to help you understand and utilize that mechanism.
The Cisco Date Code
Cisco hardware items all come with a serial number, and that number follows a specific format. If you follow the format, you can see the manufacture date for any product at a glance.
The first thing to know is that the format follows the form "LLLYYWWSSSS." There are a few different things included in this, but "YY" is a two-digit code for the year, and "WW" is a code for the week of manufacturing (which ultimately tells you the month).
It’s worth noting that the two-digit number describing the year is not the last two digits of the year the device was manufactured. Instead, it’s a two-digit code that you can then use to determine the year. The table below shows exactly how this code works:
Once you know the year for 01, you can figure out the year using the code without the need of the table above. Or, you can simply look up the numbers as needed.
As for the week code, it’s simpler. The two digits refer to the specific week in the year when the device was made. Remembering that there are 52 weeks in a year, it’s easy to see why the code runs from 1 to 52. Still, if you want an easy breakdown of which months correspond with which weeks, you’ll see that in the table below.
Finally, we can put this into practice. Let’s use a made-up serial number to see what it really looks like: ABC01291D2E. In this number, “01” is the year code, and “29” is the week code. Note that the number after “29” is part of the SSSS portion of the serial number.