ZigBee

ZigBee is a low-cost, low-power, wireless mesh networking standard. The low cost allows the technology to be widely deployed in wireless control and monitoring applications, the low power-usage allows longer life with smaller batteries, and the mesh networking provides high reliability and larger range.

The ZigBee Alliance, the standards body which defines ZigBee,[1] also publishes application profiles that allow multiple OEM vendors to create interoperable products. The current list of application profiles either published or in the works are: Home Automation, ZigBee Smart Energy, Telecommunication Applications, and Personal Home and Hospital Care.

The relationship between IEEE 802.15.4-2003 and ZigBee is similar to that between IEEE 802.11 and the Wi-Fi Alliance. The ZigBee 1.0 specification was ratified on December 14, 2004 and is available to members of the ZigBee Alliance. Most recently, the ZigBee 2007 specification was posted on October 30, 2007. The first ZigBee Application Profile, Home Automation, was announced November 2, 2007.

For non-commercial purposes, the ZigBee specification is available free to the general public.[2] An entry level membership in the ZigBee Alliance, called Adopter, costs US$ 3500 annually and provides access to the as-yet unpublished specifications and permission to create products for market using the specifications.

ZigBee operates in the industrial, scientific and medical (ISM) radio bands; 868 MHz in Europe, 915 MHz in countries such as USA and Australia, and 2.4 GHz in most jurisdictions worldwide. The technology is intended to be simpler and cheaper than other WPANs such as Bluetooth. ZigBee chip vendors typically sell integrated radios and microcontrollers with between 60K and 128K flash memory, such as the Freescale MC13213, the Ember EM250 and the Texas Instruments CC2430. Radios are also available stand-alone to be used with any processor or microcontroller. Generally, the chip vendors also offer the ZigBee software stack, although independent ones are also available.

As of 2006, the retail price of a Zigbee-compliant transceiver is approaching $1, and the price for one radio, processor, and memory package is about $3.[3] Comparatively, the price of consumer-grade Bluetooth chips is now under $3.[4]

The first stack release is now called Zigbee 2004. The second stack release is called Zigbee 2006, and mainly replaces the MSG/KVP structure used in 2004 with a "cluster library". The 2004 stack is now more or less obsolete.

Zigbee 2007, now the current stack release, contains 2 stack profiles, stack profile 1 (simply called ZigBee), for home and light commercial use, and stack profile 2 (called ZigBee Pro). ZigBee Pro offers more features, such as multi-casting, many-to-one routing and high security with Symmetric-Key Key Exchange (SKKE), while ZigBee (stack profile 1) offers a smaller footprint in RAM and flash. Both offer full mesh networking and work with all ZigBee application profiles.

ZigBee 2007 is fully backward compatible with ZigBee 2006 devices: a ZigBee 2007 device may join and operate on a ZigBee 2006 network and vice versa. Due to differences in routing options, ZigBee Pro devices must become non-routing ZigBee End-Devices (ZEDs) on a ZigBee 2006 or ZigBee 2007 network, the same as ZigBee 2006 or ZigBee 2007 devices must become ZEDs on a ZigBee Pro network. The applications running on those devices work the same regardless of the stack profile beneath them.