藍牙核心架構一

1、 Bluetooth Core Architecture Blocks （藍牙核心架構）（一）標簽： interfaceprotocolsservicesystem測試layer2012-07-26 18:50 7098人閱讀 評論(4) 收藏 舉報 分類：BlueTooth（13） 首先，第一幅圖是藍牙官網上的圖示，對應藍牙4.0版本。（2012年7月份最新更新）因為該圖不很清楚，有人重畫了下，稍微修改了其中一部分，如下圖：為便于理解，附上v1.0的架構圖示如下：為了便于理解，最后附上M$上關于藍牙協(xié)議的圖示，如

2、下圖：下面就是關于藍牙官網上文章的翻譯了，因為時間和水平有限，主要是水平有限，翻譯難免有誤差之處，歡迎斧正。（） Core System DefinitionThe Bluetooth core system covers the four lowest layers andassociated protocols defined by theBluetooth specificationas well as one common service layer protocol, theservice discovery protocol (SD

3、P) and the overall profile requirements arespecified in the generic access profile (GAP). A completeBluetooth application requires a number of additional servicesand higher layer protocols that are defined in theBluetooth specification.(這段話的理解非常重要，為了準確翻譯這段話，我還深入研究了“as well as”的用法）藍牙核心系統(tǒng)覆蓋了

4、藍牙spec中定義的最低層的四個部分以及相關協(xié)議，同時還包括一個通用服務層協(xié)議，服務發(fā)現(xiàn)協(xié)議以及在GAP中指出的全部需求。同時，一個完整的藍牙應用程序還需要其他一些附加的服務和在藍牙spe中定義的更高層的協(xié)議。BluetoothControllerThe lowest three layers aresometimes grouped into a subsystem known as the Bluetooth controller. This is a common implementation involvinga standard physical communic

5、ations interface between theBluetooth controller and remainder of theBluetooth system including the L2CAP, service layers and higherlayers (known as theBluetooth host). Although this interface is optional, the architecture is designedto allow for its existence and characteristics. The

6、Bluetooth specification enables interoperability betweenindependentBluetooth enabledsystems by defining the protocol messages exchanged between equivalent layers,and also interoperability between independentBluetooth sub-systems by defining a common interface betweenBluetooth con

7、trollers andBluetooth hosts.藍牙控制部分最底下的三層有時候被歸為一組成為一個子系統(tǒng)稱做藍牙控制器。這是一個通用的執(zhí)行部分，包括一個用于藍牙控制器和藍牙系統(tǒng)其他剩余部分之間的標準的物理通信接口，這些剩余部分包括L2CAP，服務層以及更高級的層次（常叫做藍牙host）。雖然這個接口并非必不可少，但是本架構設計上允許它的存在和特點。藍牙說明書通過定義同等層間的協(xié)議信息交換來使得獨立的藍牙系統(tǒng)之間協(xié)調工作，同時，通過定義一個藍牙控制器和藍牙host間的通用接口，保障了藍牙子系統(tǒng)之間的協(xié)調工作能力。 A number of functional block

8、sare shown and the path of services and data between these. The functionalblocks shown in the diagram are informative; in general theBluetooth specification does not define the details ofimplementations except where this is required for interoperability.很多功能塊以及他們之間的服務和數(shù)據傳輸路徑如圖所示。這些功能塊提供了很多的信息。總

9、的來說，藍牙spec不會定義執(zhí)行體之間的細節(jié)部分，除非他們之間要求協(xié)同工作。Core System Protocols andSignalingStandard interactions aredefined for all inter-device operation, where Bluetooth devices exchange protocol signaling according to theBluetoothspecification. TheBluetooth core system protocols are the radio (RF) pr

10、otocol,link control (LC) protocol, link manager (LM) protocol and logical link controland adaptation protocol (L2CAP), all of which are fully defined in subsequentparts of theBluetoothspecification. In addition, the service discovery protocol (SDP) is a servicelayer protocol required by allBluetooth

11、 applications.核心系統(tǒng)協(xié)議和信號為內部設備之間的操作定義了標準的交互流程，在這些內部操作中，根據藍牙spec藍牙設備交互協(xié)議信號。藍牙核心系統(tǒng)協(xié)議棧包括RF協(xié)議，鏈接控制協(xié)議，鏈接管理西醫(yī)和邏輯連接控制適應協(xié)議（L2CAP），這些協(xié)議在藍牙spec隨后部分中都均有定義。另外，服務發(fā)現(xiàn)協(xié)議是一個所有藍牙應用程序都需要的服務層協(xié)議。The Bluetooth core system offers services through a number ofservice access points that are shown in the diagram

12、as ellipses. These servicesconsist of the basic primitives that control theBluetooth core system. The services can be split into threetypes. There are device control services that modify the behavior and modes ofaBluetooth device,transport control services that create, modify and release t

13、raffic bearers(channels and links), and data services that are used to submit data fortransmission over traffic bearers. It is common to consider the first two asbelonging to the C-plane and the last as belonging to the U-plane. 藍牙核心系統(tǒng)為許多服務通路點（AP）提供服務，如圖中橢圓點處所示。這些服務有控制藍牙核心系統(tǒng)的基元組成。這些服務可以分成三種類型。第

14、一種是設備控制服務用于修改藍牙設備的行為和工作方式，第二種是傳輸控制服務用于創(chuàng)建、修改以及釋放通信送信單元（信道和鏈接），第三種是數(shù)據服務用于在通信送信單元上為傳送功能傳遞數(shù)據。很容易的理解前兩個屬于C層面，最后一個屬于U層面。Host to ControllerInterface (HCI): Splits Bluetooth Stack Into Controller and HostA service interface to the Bluetooth controller sub-system is defined such that theB

15、luetooth controller may be considered a standard part. In thisconfiguration theBluetoothcontroller operates the lowest three layers and the L2CAP layer is containedwith the rest of theBluetooth application in a host system. The standard interface is called the hostto controller interface (

16、HCI). Implementation of this standard serviceinterface is optional.主機和控制器接口（HCI）：劃分藍牙協(xié)議棧為控制器和主機和藍牙控制器子系統(tǒng)的服務接口定義如下：藍牙控制器被認為是一個標準的部分。在一個主機系統(tǒng)中，藍牙控制器操作最底下的三層和L2CAP的這種配置包含在藍牙應用程序的其他部分。標準接口稱為HCI。對這個標準服務的接口的實現(xiàn)是可有可無的。As the Bluetooth architecture is defined with the possibility of aseparate host a

17、nd controller communicating through an HCI, a number of generalassumptions are made. TheBluetooth controller is assumed to have limited data buffering capabilities incomparison with the host. Therefore the L2CAP layer is expected to carry outsome simple resource management when submitting L2CAP

18、 PDUs to the controllerfor transport to a peer device. This includes segmentation of L2CAP SDUs intomore manageable PDUs and then the fragmentation of PDUs into start andcontinuation packets of a size suitable for the controller buffers, andmanagement of the use of controller buffers to ensure avail

19、ability for channelswith quality of service (QoS) commitments.既然藍牙架構可以定義成通過HCI通信的一個主機和一個控制器，所以就須假設一些通用的東西。和主機相比，假設藍牙控制器有著有限的數(shù)據緩存能力。因此就期望在給一個對等的設備傳輸數(shù)據時，當遞交L2CAPPDU給控制器過程中，L2CAP層來執(zhí)行一些簡單的資源管理工作。這些工作包括把L2CAP SDU分割成更多的可以管理的PDU以及進一步把PDU細化成更小的部分，這些部分可以適合在控制器緩沖中進行開始和延續(xù)大小的包，還有為了卻確保信道的QoS責任的可行性進行的對控制器緩沖利用的管理工

20、作。 Error Detection in L2CAP LayerThe baseband layer providesthe basic ARQ protocol in Bluetooth technology. The L2CAP layer can optionally provide a further errordetection and retransmission to the L2CAP PDUs. This feature is recommended forapplications with requirements for a low pro

21、bability of undetected errors inthe user data. A further optional feature of L2CAP is a window-based flowcontrol that can be used to manage buffer allocation in the receiving device.Both of these optional features augment the QoS performance in certainscenarios.LCAP層的錯誤檢測在藍牙技術中，基帶層提供基本的ARQ協(xié)議。L2CAP可以

22、有選擇性地提供深層次的錯誤檢測和對L2CAPPDU的重傳機制。這個特性對一些應用程序有推薦作用，這些應用程序在對用戶數(shù)據沒有檢測到錯誤存在低的可能性有著一定的要求。L2CAP的的另外一個可能的特性是，基于窗口的流控制在接受設備端可被應用來管理緩沖分配。這兩個可選擇性的特性在一定場景提高了QoS的性能。 Although these assumptions maynot be required for embedded Bluetooth technology implementations that combine all layers in a single s

23、ystem,the general architectural and QoS models are defined with these assumptions inmind, in effect a lowest common denominator. 對于那些將所有的層聯(lián)合在一個獨立系統(tǒng)的嵌入式藍牙技術來說，在實現(xiàn)來上，雖然這些假設可能并沒有要求，依據這些假設的通用架構和QoS模式已經在大腦中形成，實際上是最小公分母。 Testing Interfaces: RF and Test Control Interface (TCI)Automated conformanc

24、e testingof implementations of the Bluetooth core system is required. This is achieved by allowing the tester tocontrol the implementation through the RF interface, which is common to allBluetooth systems, and through the test control interface(TCI), which is only required for conform

25、ance testing.測試接口：射頻和測試控制接口藍牙核心系統(tǒng)實現(xiàn)的自動化一致性測試是必須的。這個測試是通過允許測試人員通過射頻接口來控制它的實現(xiàn)來得到的，這對所有的藍牙系統(tǒng)來說很普通的，并且通過這個測試控制接口（TCI），這是在一致性測試中唯一要求的。 The tester uses exchanges withthe implementation under test (IUT) through the RF interface to ensure thecorrect responses to requests from remote devices. The tester controls the IUTthrough the TCI to cause the IUT to originate exchanges through the RF interfaceso that these