Audio / Video Control Transport Protocol (AVCTP)
AVCTP describes the transport mechanisms to exchange messages for controlling A/V devices.
Usage Scenario
AVCTP describes the mechanism that would allow different A/V devices to talk to each other, such as a Bluetooth enabled remote control and a Bluetooth enabled television.
Example Products
Here are a few examples of the types of devices that you might find using the AVCTP:
- PC
- Portable Player
- Video Camera
- TV
- Video monitor
Getting Technical
Operations Between Devices
AVCTP uses point-to-point signalling over connection-oriented L2CAP channels that have first to be set up between both devices. L2CAP channels are the most suitable for the support of A/V applications, which require dedicated transport services for A/V content streaming and feature control on the same link
AVCTP is used when a command message and possible response messages are sent between two Bluetooth enabled devices. The device that initiates an AVCTP transaction by sending a command message is called the controller (CT). The command message is transmitted to the remote device that is called the target (TG) for this transaction. The target returns zero or more responses back to the controller according to the condition of the target or the type ofthe initiated transaction.
In the above figure and the figure to the left, AVCTP is one of the protocol specifications used in the context of audio and video applications. AVCTP specifies the protocol used to transport the control messages (command and response) between compliant devices in A/V applications.
All A/V protocols are specified independently so that a remote controller function maybe implemented in a non-streaming device while an A/V streaming device may not support A/V controls. However, this protocol could coexist in the same device with other A/V protocols and should be able to share a common ACL link.
Need more? View the Audio / Video Control Transport Protocol (AVCTP).
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