SAE J2366/2_200111

1 Scope
2 References
  2.1 Applicable publications
       2.1.1 SAE publications
  2.2 Related publications
       2.2.1 SAE publications
       2.2.2 CAN publications
       2.2.3 ISO publications
3 Definitions
  3.1 ATID
  3.2 Bit
  3.3 Clear
  3.4 Collision
  3.5 Controlling layer
  3.6 Dominant
  3.7 Frame
  3.8 Frame Collision Counter Threshold, FCC Threshold
  3.9 Halt state
  3.10 HDLC
  3.11 IDB and IDB-C
  3.12 Insane node
  3.13 ITS
  3.14 Key state
       3.14.1 Key off state
       3.14.2 Key on state
       3.14.3 Key pulse
  3.15 LLC (Logical Link Control)
  3.16 MAC (Media Access Control)
  3.17 Node
       3.17.1 Active node
       3.17.2 Not active node
       3.17.3 Not present node

This SAE Recommended Practice details the Link Layer of the Intelligent Transportation Systems (ITS) Data Bus, which is generally intended for in-vehicle use.

This SAE Recommended Practice details the Link Layer of the Intelligent Transportation Systems (ITS) Data Bus, which is generally intended for in-vehicle use.The ITS Data Bus (IDB) is a non-proprietary token passing bus, designed to allow disparate consumer, vehicle, and commercial electronic components to communicate and share information across a standard, open data bus. This first version of the IDB is called IDB-C.This Recommended Practice describes the Link Layer of the IDB-C, as shown in Section 1. Below the Link Layer of the IDB-C is the CAN 2.0B Link Layer. The Physical Layer of the IDB-C incorporates the Physical Layer as specified by SAE J2366-1 and J2590.The IDB-C Link Layer is logically divided into two functional sub-layers, viz., Logical Link Control (LLC) and Media Access Control (MAC). However, these are logical groupings that re-use some of the same bits within the CAN 2.0B frame for efficiency.The MAC sub-layer handles all media access functions, such as virtual token handling, addressing, and notifications of IDB-C configuration changes to other MAC layers on the IDB-C.The LLC sub-layer provides the mechanisms to send and receive point-to-point or broadcast frames to other LLC sub-layers on the IDB-C. In addition, the LLC provides an Alternate Transport Identifier (ATID) allowing more than one set of higher layer protocols to be used on a single Node.