GB/T 39851.2-2021 English PDF (GBT39851.2-2021)

Delivery: 3 seconds. Download true-PDF + Invoice.
Get QUOTATION in 1-minute: Click GB/T 39851.2-2021
Historical versions: GB/T 39851.2-2021
Preview True-PDF (Reload/Scroll if blank)

GB/T 39851.2-2021: Road vehicles -- Diagnostic communication over Controller Area Network (DoCAN) -- Part 2: Transport protocol and network layer services
GB/T 39851.2-2021
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 43.040
T 36
Road vehicles - Diagnostic communication over
Controller Area Network (DoCAN) - Part 2:
Transport protocol and network layer services
(ISO 15765-2:2016, MOD)
ISSUED ON: MARCH 09, 2021
IMPLEMENTED ON: OCTOBER 01, 2021
Issued by: State Administration for Market Regulation;
Standardization Administration of the PRC.
Table of Contents
Foreword ... 3 
Introduction ... 5 
1 Scope ... 6 
2 Normative references ... 7 
3 Terms, definitions and abbreviated terms ... 7 
4 Conventions ... 9 
5 Overview ... 9 
6 CAN data link layer extension ... 12 
7 Network layer overview ... 15 
8 Network layer services ... 17 
9 Transport layer protocol ... 27 
10 Data link layer usage ... 53 
Annex A (Normative) Use of normal fixed and mixed addressing with data link
layer according to SAE J1939 ... 61 
Annex B (Normative) Reserved CAN ID ... 64 
Bibliography ... 65 
Foreword
GB/T 39851 "Road vehicles - Diagnostic communication over Controller Area
Network (DoCAN)' has issued and plans to issue the following parts:
- Part 2: Transport protocol and network layer services;
- Part 3: Requirements for emission-related systems;
This Part is Part 2 of GB/T 39851.
This Part is drafted in accordance with the rules given in GB/T 1.1-2009.
This Part uses the redraft law to modify and adopt ISO 15765-2:2016 "Road
vehicles - Diagnostic communication over Controller Area Network (DoCAN) -
Part 2: Transport protocol and network layer services".
Compared with ISO 15765-2:2016, the structure of this Part has been adjusted
as follows:
- For the convenience of readers, the subclause composed of multiple
paragraphs is subdivided into several articles without title;
- According to the content added in Clause 5, add 5.1 "Open Systems
Interconnection (OSI) model", 5.2 "Diagnostic network architecture", and
5.3 "Overview of DoCAN use cases". Adjust the content of Clause 5 of the
international standard to 5.1.8.
The technical differences between this Part and ISO 15765-2:2016 and their
reasons are as follows:
- ADD the content of "Open Systems Interconnection model" (see 5.1);
- ADD the content of "Diagnostic network architecture" (see 5.2);
- ADD the content of "Overview of DoCAN use cases" (see 5.3).
This Part has made the following editorial change:
- In accordance with the requirements of GB/T 1.1-2009, standardize the
compilation of the "Scope" clause.
This Part was proposed by Ministry of Industry and Information Technology of
the PRC.
Road vehicles - Diagnostic communication over
Controller Area Network (DoCAN) - Part 2:
Transport protocol and network layer services
1 Scope
This Part of GB/T 39851 specifies a transport protocol and network layer
services tailored to meet the requirements of CAN-based vehicle network
systems on controller area networks as specified in ISO 11898-1:2015. It has
been defined in accordance with the diagnostic services established in ISO
14229-1 and ISO 15031-5.
This Part applies to the diagnostic services defined in ISO 14229-1 and ISO
15031-5, as well as other communication needs for in-vehicle networks.
ISO 11898-1:2015 specifies variable length CAN frames with a maximum
payload size dependent on the protocol device used. A CLASSICAL CAN
protocol device can transmit/receive frames with payload sizes ranging from 0
bytes to 8 bytes per frame. A CAN FD (flexible data rate) protocol device can
transmit/receive frames with payload sizes from 0 bytes to 64 bytes. A CAN FD
protocol device is also capable of transmitting/receiving CLASSICAL CAN
frames.
The diagnostic communication over controller area network (DoCAN) protocol
supports the standardized service primitive interface as specified in ISO 14229-
2.
This Part provides the transport protocol and network layer services to support
different application-layer implementations such as
- enhanced vehicle diagnostics (emissions-related system diagnostics
beyond legislated functionality, non-emissions-related system diagnostics),
- emissions-related on-board diagnostics (OBD) as specified in ISO 15031,
- world-wide harmonized on-board diagnostics (WWH-OBD) as specified in
ISO 27145, and
- end of life activation on on-board pyrotechnic devices (as specified in ISO
26021-1).
The transport protocol specifies an unconfirmed communication.
2 Normative references
The following documents are indispensable for the application of this document.
For the dated references, only the editions with the dates indicated are
applicable to this document. For the undated references, the latest edition
(including all the amendments) are applicable to this document.
ISO/IEC 7498-1 Information technology - Open systems interconnection -
Basic reference model - Part 1: The basic model
ISO 11898-1:2015 Road vehicles - Controller area network (CAN) - Part 1:
Data link layer and physical signalling
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC
7498-1, ISO 11898-1:2015 and the following apply.
3.1.1
CAN frame data length; CAN_DL
Physical length of CAN frame data/payload in bytes.
3.1.2
Transmit data link layer data length; TX_DL
Configures the maximum usable payload length in bytes of the data link layer
in the transmitter for the application that implements the network layer as
defined in this Part.
Note: The TX_DL is a fixed configuration value on the sender side for the PDU
transmission.
3.1.3
Received data link layer data length; RX_DL
Retrieved maximum usable payload length in bytes of the data link layer in the
receiver for the application that implements the network layer as defined in this
Part.
Note: The RX_DL value is retrieved from the FirstFrame (FF) CAN_DL of a segmented