To check your PID press the win key and pause at the same time, or open system properties through the control panel, scroll down to activation section and look at the PID It will look something like this 12345-067-1234567-54321, the portion you are interested in is the three digit section, if it matches or is within one or two digits of the examples below you probably have an MSDN key.
065, 066, 067, 068 for Ultimate, 220, 221 area for Pro and the 230, 231, 221, 232 area for premium, there are probably others but they should be close to those posted
About MSDN or TechNet Product Keys
They are genuine Microsoft product keys, they are actually retail licenses, but it is intended for a particular product channel either the Microsoft Software Developer Network (MSDN) or TechNet for IT Professionals who pay a subscription fee. The main purpose is for evaluation purposes. The great thing about them, unlike trial Microsoft software, MSDN or TechNet keys don't expire. Because the agreement under which the subscription is provided is a single license, none of the software should be distributed outside of it. Even though its $50,000 worth of licenses, it is for one person only to use and no one else. Unfortunately, regardless of the licensing terms, persons still abuse the program, either giveaway product keys or resell it on auction sites. Microsoft licenses it in good faith that customers won't do so, but I guess human nature wins out.