No, the ZigBee SPECIFICATION does not define a transport layer. Since most ZigBee data exchanges target simple and small messages, the QUESTION of ensuring end-to-end data delivery has been left to the PRODUCT vendor. The latter can choose to INCLUDE that capability as part of its application.

Some stack vendors, such as Ember, provide an additional transport layer that guarantees reliable end-to-end messaging and simplifies application development. This feature is however not specified in the standard and will therefore be used in combination with private application profiles.

No, the ZigBee specification does not define a transport layer. Since most ZigBee data exchanges target simple and small messages, the question of ensuring end-to-end data delivery has been left to the product vendor. The latter can choose to include that capability as part of its application.

Some stack vendors, such as Ember, provide an additional transport layer that guarantees reliable end-to-end messaging and simplifies application development. This feature is however not specified in the standard and will therefore be used in combination with private application profiles.