scatternets

Scatternets are a type of Bluetooth network that interconnects multiple piconets to form a larger, overlapped network. A piconet is a small Bluetooth network consisting of one master device and up to seven active slaves, all sharing a common time-division and frequency-hopping sequence. A scatternet arises when a single device participates in more than one piconet, effectively acting as a bridge between them. In typical scenarios, a bridging device may serve as a master in one piconet while acting as a slave in another, or switch between roles to communicate with different masters.

The concept relies on the ability of devices to time-share participation across piconets. Because each piconet is synchronized to its master’s clock and hopping pattern, coordinating activity across multiple piconets adds complexity. Bridging devices must manage scheduling, which can introduce extra latency and potentially reduce throughput. The Bluetooth specification does not prescribe a single standard scatternet topology or a guaranteed level of interoperability, and implementations from different vendors have varied in reliability and ease of use.

In practice, scatternets have found limited deployment in consumer gear, with most commercial Bluetooth designs focusing on discrete piconets or newer mesh-based approaches. Scatternet research and some specialized applications—such as ad hoc links between computers and peripherals or sensor networks—have explored the potential benefits of larger, connected Bluetooth networks. Security considerations include ensuring consistent pairing and encryption keys across piconets, since bridging devices must maintain trust relationships across multiple links.