If you’re looking to get any platform, product, etc. ZigBee certified, you probably know that you need to check for 802.15.4 compliance before you move on to the higher layers. However did you know that ZigBee does not mandate the implementation of the full 802.15.4 MAC layer? Some functions of the 802.15.4 MAC are actually even prohibited in ZigBee and their use will cause your platform to be non-compliant. This not only reduces the testing you have to do, but also reduces code size and complexity that is not needed for your stack. Features such as GTS, MAC security, beacon networking, and PAN ID conflict on the MAC layer are just thrown out. In other words, ZigBee will only ask that you test a relatively small portion of the 802.15.4 MAC which should come as good news to all of you out there worrying about fitting all of this code in small memory chips to cut cost!