Airlogic ABM-400 Bedienungsanleitung PDF herunterladen (Seite 45)

- 45 -

The Link Manager Protocol is the language which the link managers in each Bluetooth device

use to speak to one another. The Link Managers set up secure transmissions using what is called

a challenge-response system. This encryption and trust allows piconets to form. The Link

Manager also oversees prioritizing of bandwidth for the disparate demands of asynchronous data

traffic, and the more immediate needs of audio traffic. Link Managers also provide a control on

power use, through power conservation based on device proximity. Reductions in broadcast

strength determined by the Link Manager, can save hours worth of uptime.

The Logical Link Control and Adaptation Protocol (L2CAP) hides lower level details from the

higher levels. The changes in frequency are masked at this level, allowing the middleware

protocols to remain blissfully ignorant of Bluetooth's frequency hopping. Packets from higher

level protocols are also broken up at this level into more bite-sized chunks, suitable for the

Baseband/Radio Protocols.

The HCI Layer is an optional piece of the Transport Layer. In order to facilitate

communication between the lowest and highest levels of the protocol stack, the HCI , or Host

Controller Interface allows the Application Group of protocols to interact with the baseband and

radio layers through a standardized interface. The actual Bluetooth devices as well as

applications that may interact with them will be created by several different vendors, making the

HCI layer an important standard that will assist companies in implementing Bluetooth devices.

The Middleware Protocol Group connects the Transport level protocols with the protocols

spoken by Bluetooth aware applications. The Middleware group consists of the RFCOMM

protocol, the IrDa Interoperability protocol, the Service Discovery Protocol, and the Telephony

Control Protocol.

1 2 ... 40 41 42 43 44 45 46 47 48 49 50 ... 147 148

Keine Kommentare

Airlogic ABM-400 Bedienungsanleitung Seite 45