Performance of Bluetooth Bridges in Scatternets with Limited Service Scheduling

The performance of two Bluetooth piconets linked through a bridge device is analyzed using the tools of queueing theory. We analyze both possible cases, i.e., when the bridge device is the master in one of the piconets and a slave in the other (MS bridge), as well as when the bridge device is the slave in both of the piconets (SS bridge). Analytical results are derived for the probability distribution of access delay (i.e., the time that a packet has to wait before being serviced) and end-to-end delay, for both intra- and inter-piconet bursty traffic. The scatternet with an SS bridge was found to provide lower end-to-end delay for local traffic as well as lower access delay, while the scatternet with an MS bridge offers lower end-to-end delay for non-local traffic. The scatternet with an SS bridge was also found to be less sensitive to increased probability of non-local traffic and low values of time interval between bridge exchanges, than its counterpart with an MS bridge. All analytical results have been confirmed through simulations.