Analyzing the Device Discovery Phase of Bluetooth Scatternet Formation Algorithms

Abstract

we study in this paper the impact of the modifications introduced in version 1.2 of the Bluetooth specifications on Bluetooth Scatternet Formation (BSF) algorithms. Up to now, the effect of these modifications on BSF algorithms had not been analyzed. We show that: 1) Bluetooth ver1.2 and upward have a major positive effect on static BSF algorithms (i.e. those which require an external device discovery phase). We conducted some experiments on a common device discovery technique for static BSF algorithms and compared its performance using Ver1.2 and Ver1.1 (the latter is used in most BSF studies). We found that this technique, using ver1.2, generates a connected topology about 3.5 times faster than it does using ver1.1. It also discovers about 20% more edges. 2) Dynamic algorithms, on the other hand, are not affected by these modifications. This will be proven using some experiments and some analytical arguments. These results give more applicability to static BSF algorithms and call for more research on dynamic BSF algorithms.

Towards better understanding of the behaviour of Bluetooth networks distributed algorithms

“…Moreover, we found in Ref. [8] that there is no significant statistical difference between the connectivity times of ALTERNATE and LIM-ALTERNATE in all versions. The details of the experiments are not included in this paper and can be found in Ref.…”

“…In Refs [6,9], an analysis of the inquiry procedures is done to obtain faster neighbour discovery algorithms. Other authors proposed to improve the inquiry procedures by modifying the specifications of device discovery [2,26].…”

Some side effects of FHSS on Bluetooth networks distributed algorithms

“…Link Establishment Procedures in ver 1.1 and ver 1. 2 Some modifications on the INQUIRY procedures appeared in Bluetooth ver1.2 and above. These modifications, although small, have a substantial impact on a large number of BSF algorithms (but not all); since they reduce the amount of time to establish a link between two nodes.…”

“…Although it presented solutions to many problems, it introduced as well some new problems. One of these problems is the relative slow execution time of distributed algorithms running over Bluetooth networks (see Chapter 3 of [2]). We believe that this problem is related to the misunderstanding and unawareness of the side effects of the communication techniques used in Bluetooth.…”

“…We concentrate in this paper on the device discovery procedure. For more details about the experiments included in this paper and the problems introduced to the link establishment operation, the reader is referred to our work in [2]. (See [17] for shorter version of this paper.…”