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9.8.5 Dial-up Networking Profile (DUN)
DUN provides a standard to access the Internet and other dial-up services over Bluetooth
technology. The most common scenario is accessing the Internet from a laptop by dialing
up on a mobile phone wirelessly. It is based on SPP and provides for relatively easy
conversion of existing products, through the many features that it has in common with the
existing wired serial protocols for the same task. These include the AT command set
specified in ETSI 07.07 and PPP.
Like other profiles built on top of SPP, the virtual serial link created by the lower layers of
the
Bluetooth protocol stack is transparent to applications using the DUN profile. Thus, the
modem driver on the data-terminal device is unaware that it is communicating over
Bluetooth technology. The application on the data-terminal device is similarly unaware
that it is not connected to the gateway device by a cable.
DUN describes two roles, the gateway and terminal devices. The gateway device provides
network access for the terminal device. A typical configuration consists of a mobile phone
acting as the gateway device for a personal computer acting as the terminal role.
Source: Bluetooth SIG, URL:
http://www.bluetooth.com/Bluetooth/Technology/Works/DUN.htm
9.8.6 Object Push Profile (OPP)
OPP defines the roles of push server and push client. These roles are analogous to and
must interoperate with the server and client device roles that GOEP defines. It is called
push because the transfers are always instigated by the sender (client), not the receiver
(server). OPP focuses on a narrow range of object formats to maximize interoperability.
The most common acceptable format is the vCard. OPP may also be used for sending
objects such as pictures or appointment details.
Source: Bluetooth SIG, URL:
http://www.bluetooth.com/Bluetooth/Technology/Works/OPP.htm
9.8.7 Advanced Audio Distribution Profile
A2DP describes how stereo-quality audio can be streamed from a media source to a sink.
The profile defines two roles of an audio device: source and sink.
 Source (SRC) – A device is the SRC when it acts as a source of a digital audio
stream that is delivered to the SNK of the Piconet.
 Sink (SNK) – A device is the SNK when it acts as a sink of a digital audio stream
delivered from the SRC on the same Piconet.
A2DP defines the protocols and procedures that realize distribution of audio content of
high-quality in mono or stereo on ACL channels. The term “advanced audio,” therefore,
should be distinguished from “Bluetooth audio,” which indicates distribution of narrow
band voice on SCO channels as defined in the baseband specification.
This profile relies on GAVDP. It includes mandatory support for low complexity subband
codec (SBC) and supports optionally MPEG-1,2 Audio, MPEG-2,4 AAC and ATRAC.
The audio data is compressed in a proper format for efficient use of the limited bandwidth.
Surround sound distribution is not included in the scope of this profile.