wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

49-8 Industrial Communication Systems
49.4.1 Four Bluetooth General Profiles
The Bluetooth specifications define four general profiles on which usage models and all other profiles
are based [3]. Those are the GAP, the Serial Port Profile (SPP), the Service Discovery Application Profile
(SDAP), and the Generic Object-Exchange profile (GOEP).
All foundation profiles are based in the GAP that outlines a set of comprehensive key features that
may or may not be used in the specific governing profile. Hence, the GAP provides the foundation upon
which other profiles can be based. While defining profile implementation, it is important to emphasize
the features (degrees of adoption) of that profile. Those features are described as mandatory (M),
optional (O), conditional (C), excluded (S), and not applicable (N/A).
Serial Port Profile (SPP) defines how devices can be set up for serial port emulation using Bluetooth
Radio Frequency Communications (Bluetooth RFCOMM). RFCOMM is a simple transport
protocol that emulates a virtual serial port between Bluetooth devices using RS-232 control
signaling.
Service Discovery Application Profile (SDAP) defines the procedures used to discover services registered
on other Bluetooth devices. SDAP is responsible for both known service and general
service searches and uses only connection-oriented channels (no L2CAP). SDAP requires the
Service Discovery Protocol (SDP).
Generic Object-Exchange Profile (GOEP) defines the requirements that Bluetooth devices must
meet to support object exchange (OBEX) usage models. Usage models, such as file transfer and
synchronization are based on this profile. The GOEP depends on the Serial Port Profile for
object exchange and describes the establishment of an OBEX session between the client and
the server, and PUT/GET (push/pull of a data object to/from the server).
49.4.2 Bluetooth General Profiles
Bluetooth profiles as defined by Bluetooth SIG are general behaviors through which Bluetooth-enabled
devices communicate with other devices [1]. By following the guidance provided in Bluetooth specifications,
developers can create applications to work with other devices also conforming to the Bluetooth
specification. At a minimum, each profile specification contains information on the following topics:
dependencies on other profiles, suggested user interface formats, and specific parts of the Bluetooth
protocol stack used by the profile [5–7].
There are currently 25 Bluetooth officially adopted profiles. Most of the Bluetooth profiles were introduced
with the Bluetooth Core Specification Version 1.1. The Bluetooth SIG governs the development of
new Bluetooth profiles.
In order for one Bluetooth device to connect to another, both devices must share at least one of the
same Bluetooth profiles. For example, if you want to use a Bluetooth headset with your Bluetoothenabled
cell phone, both devices must use the Headset (HS) profile (defined below). To perform its task,
each profile uses particular options and parameters at each layer of the stack. This may include an outline
of the required service record, if appropriate. A brief outline of currently defined profiles within the
current Bluetooth specification follows [8]:
Advanced Audio Distribution Profile (A2DP) describes how stereo quality sound can be streamed
from a media source to a sink.
Audio/Video Control Transport Protocol (AVRCP) is designed to provide a standard interface to
control TVs, hi-fi equipment, etc. A single remote control (or another device) should be able to
control all the A/V equipment to which a user has access.
Basic Imaging Profile (BIP) defines how an imaging device can be remotely controlled, how an
imaging device may print, as well as how an imaging device can transfer images to a storage
device.
© 2011 by Taylor and Francis Group, LLC