Device Addresses in ZigBee

Every device in a ZigBee network has two addresses — its globally unique 64-bit address, called the EUI64 or IEEE 64-bit address, and its PAN-unique 16-bit address, or short address.

64 bit addresses

The EUI64 is uniquely allocated by the IEEE to companies which then use them on their networking devices. Ember allocates a single EUI64 address to each chip at manufacturing time — this may be overridden (though not erased) at manufacturing time if desired.

16 bit addresses

16 bit addresses are assigned when the device joins the network and are intended to be unique within the network. They are not guaranteed to be unique, however, so there is a conflict resolution mechanism that will detect when a conflict arises and cause one or both of the conflicting devices to choose a new 16 bit address.

Usage of each type of address

Because 64 bit addresses are globally unique, they can be used to identify a particular device in cases where the 16 bit address is not known:

• When a device joins a new network or rejoins a network, it may need a new 16-bit address.
• When a 16-bit address conflict is resolved, one or both of the conflicting devices may have new 16-bit addresses.

However, a 64 bit address consumes a large amount of bandwidth and memory, so the 16 bit address is used for transient operations such as message transmission and route storage purposes. When a device must be uniquely identified over long periods of time, the application should arrange to store the 64 bit address instead of or addition to the 16 bit address.

Translation between address types

ZigBee provides ways of discovering one address if you know the other, through the ZDO.