Adaptation protocols
Last updated
Last updated
Link Manager.
Carries out link setup, above baseband, with authentication, link configuration and other protocols.
Support protocol multiplexing.
BT may support other protocols besides IP.
Segmenting and reassembly.
Link Layer Control & Adaptation (L2CAP).
Link control protocol, provides connection-oriented and connectionless data services to upper layer protocols.
Handles ACL and SCO connections.
Handle QoS specifications per connection (logical channel).
Manages concepts as “group of connections”.
Host Controller Interface (HCI).
Allows command line access to the baseband layer and LM for control and status information.
Current interfaces: USB; UART; RS-232.
Made up of three parts:
HCI firmware, HCI driver, Host Controller Transport Layer.
SDP: Service Discovery Protocol.
OBEX: Facilitates binary transfers between BT devices.
TCP-BIN: Telephony-control protocol binary (call control).
Service Discovery Protocol (SDP).
Provides a way for applications to detect which services are available and their characteristics.
Protocol question <=> answer.
(search and browsing of services).
Defines a format for service registry.
Information provided by the service attributes, a name (ID) + value.
IDs can be universal (UUID).
Protocol reusage.
BT aims to reuse older protocols (e.g. WAP, OBEX–IrDA).
Interaction with applications and phones, as commonly done before.
RFCOMM.
Based on GSM TS07.10.
Emulates a serial port, supporting all traditional applications that were able to use a serial port.
Supports multiple ports over a single physical channel between two devices.
Telephony Control Protocol Spec (TCS).
Handles call control (setup, release).
Group management for gateways, serving multiple devices.
Audioconference, e.g.
