Standard No.:	JT/T 809-2011
English Name:	GNSS system for operating vehicles - General specifications for data exchange between platforms
Chinese Name:	道路运输车辆卫星定位系统 平台数据交换
Professional Classification:	JT    Professional Standard - Transport
Issued by:	Ministry of Transport
Issued on:	2011-05-23
Implemented on:	2011-8-1
Status:	superseded
Superseded by:	JT/T 809-2019 GNSS for operating vehicles-General specifications for data exchange between platforms
Superseded on:	2019-7-1
Language:	English
File Format:	PDF
Word Count:	17000 words
Price(USD):	340.0
Delivery:	via email in 1 business day

This standard was drafted according to the rules given in GB/T 1.1-2009. This standard was proposed and is under the jurisdiction of National Technical Committee on Road Transport of Standardization Administration of China. Drafting organizations of this standard: China Transport Telecommunications & Information Center, Research Institute of Highway Ministry of Transport and Fujian Provincial Communications Department. Chief drafting staffs of this standard: Liu Jian, Cai Fengtian, Luo Guanwei, Feng Quan, Liu Yingji, Liang Jinyan, Wang Hongyu, Zhou Yi, Qiu Shejin, Niu Wenjiang, Dong Xuan, Lin Yuanhong, He Fanglin, Li Wenliang, Hong Maozhi, Li Mingying, Zhang Xuewen, Shen Bing and Shang Jiang. GNSS System for Operating Vehicles - General Specifications for Data Exchange between Platforms 道路运输车辆卫星定位系统 平台数据交换 1 Scope This standard specifies technical requirements for data exchange between monitoring and management platforms of the GNSS system for operating vehicles, including communication mode, safety certificate, function realization process, protocol message format and data entity format. This standard is applicable to data exchange between monitoring and management platforms of GNSS system for operating vehicles. 2 Normative References The following references are indispensable for the application of this standard. For dated reference, only the dated editions apply. For the undated normative references, the latest editions (including all amendments) apply. GB/T 2260 Codes for the Administrative Divisions of the People's Republic of China GB/T 19056 Vehicle Travelling Data Recorder JT/T 415-2006 Electronic Government Platform for Administration of Road Transportation - Cataloguing and Coding Rules JT/T 808-2011 GNSS System for Operational Vehicles - General Specifications for Vehicle Terminal Communication Protocol and Data Format 3 Terms, Definitions and Abbreviations 3.1 Terms and Definitions For the purpose of this standard, the following terms and definitions apply. 3.1.1 Number plate The number plate of the motor vehicle issued by the public security traffic management department, excluding color of the license plate, for example, Beijing AJ 3030. 3.1.2 Superior platform Government monitoring and management platform that provides access to other platforms. 3.1.3 Inferior platform Monitoring and management platforms, in the enterprise monitoring and management platform and government monitoring and management platform, that access to the superior platform. 3.1.4 Vehicle's positioning information A general term for the current vehicle position information and vehicle warn state information received from the vehicle terminal to the navigation satellite and delivered to the surveillance & control center, including latitude/longitude, speed and direction. 3.1.5 Vehicle's dynamic information Relevant vehicle information generated during the operation and traveling, including vehicle's positioning information, traveling state, personnel, goods and line information. 3.1.6 Vehicle's static information Vehicle's administration and operation management information that is related to the road transportation and operation activities and remains constant during a given period, including operating vehicle, the owner, employees, operation management organization and operation line information. 3.1.7 Main links Two TCP protocol-based virtual channels are adopted between superior and inferior platforms, including one-way uplink virtual channel constructed after the inferior platform, as the TCP server, is successfully connected to the TCP client of the superior platform. 3.1.8 Subordinate links Two TCP protocol-based virtual channels are adopted between superior and inferior platforms, including one-way downlink virtual channel constructed after the superior platform, as the TCP client, is successfully connected to the TCP server of the inferior platform. 3.2 Abbreviations For the purpose of this standard, the following abbreviations apply. CCITT - Consultative Committee for International Telegraphy and Telephony CRC - Cyclic Redundancy Check CRC 16-CCITT - CRC-16 Code of CCITT Standard UTC - Universal Time Coordinated 4 Technical Requirements 4.1 Communication mode Double-link communication mode is adopted between the superior platform and the inferior platform; and the specific requirements are as follows: a) TCP protocol-based long connection mode is adopted as the communication mode between the superior and inferior platforms; b) The superior platform provides IP address, port No., user name and password for the access of the inferior platform; c) The inferior platform initiates a request for the connection of the main link to the superior platform; after the main link is successfully established, the superior platform initiates a request for the connection of the subordinate link to the inferior platform; d) The inferior platform may send data to the superior platform via main link while the superior platform may send data to the inferior platform via subordinate link; e) In case of any interruption in either of the main or subordinate link, all the data will be transmitted via the other link; when the interrupted link is recovered, the data continues to be transmitted from the two links according to those stipulated in this standard; f) The communication link is sent via the TCP client to maintain the connection of data package testing link and realize reliable connection between the links. 4.2 Safety certification According to communication mode proposed in Section 4.1, the superior platform carries out the safety verification on the access request of the inferior platform so as to guarantee that reliable and creditable communication link is established; however, the inferior platform needn't carry out safety verification on the access request of the superior platform. Safety verification process of the superior platform for the inferior platform shall comply with the following requirements: a) The superior platform assigns corresponding access code, access user name, password and data encryption/decryption parameters to the inferior platform; b) When the inferior platform and the superior platform are connected with each other, the "log-in request" message is sent. After the superior platform receives the connection request of the inferior platform, it will firstly verify the requested IP address. In case of any inconsistency between the requested IP address and stipulated access IP address, it will return to the verification failure result. Secondly, the superior platform verifies the access code, user name and password of the inferior platform and returns corresponding result value to the inferior platform according to verification results. c) Encryption mode may be adopted for the data transmission between the superior and inferior platforms so as to realize instant encryption of the transmission data; specific encryption algorithm is in accordance with those specified in Article 4.4.7. 4.3 Function realization process 4.3.1 Link management process 4.3.1.1 Log-in and hold request of main link from inferior platform to the superior platform. 4.3.1.1.1 Log-in process of main link for the inferior platform Log-in process of main link for the inferior platform shall comply with the following requirements: a) The inferior platform sends a log-in request to the superior platform. The log-in request data package includes platform access code, log-in user name and password, TCP service IP address and port No. necessary for the establishment of subordinate link; b) The superior platform carries out safety certification on the log-in request of the inferior platform and records log-in conditions in the log. If the certification is successful, response to successful log-in will be given; otherwise, the response to log-in failure will be given and failure reason code will be given. c) After the inferior platform successfully logs in the superior platform, the superior platform requests to establish connection with the subordinate link according to the TCP service IP address and port No. provided during the log-in of the inferior platform; d) After successful establishment of the subordinate link, follow-up downlink data package may be sent from the subordinate link. 4.3.1.1.2 Hold process of main link Hold process of main link shall comply with the following requirements: a) After successful log-in of the inferior platform, in case of any application service data package transmission between superior platforms, hold data package of the main link need not be sent; otherwise, the inferior platform shall send one hold request data package of the main link to the superior platform every 1min so as to keep link connection; b) If there is without application data package transmission and the superior platform fails to receive the hold request data package of the main link sent from the inferior platform for consecutive 3min, it shall be considered that its connection with the inferior platform is interrupted and it will initiate to interrupt the main link of data transmission; c) If there is without application data package transmission and the superior platform fails to receive the hold acknowledge data package of the subordinate link sent from the superior platform for consecutive 3min, it shall be considered that its connection with the superior platform is interrupted and it will initiate to interrupt the subordinate link of data transmission; 4.3.1.2 Log-out request of main link from inferior platform to superior platform When the inferior platform initiates to exit, it will firstly send a log-out request of the main link. After the superior platform receives it, it will return to the link, log out the response and record it in the log. Then the superior platform interrupts the main link. 4.3.1.3 Inferior platform's initiative closure of the main-subordinate link connection with the superior platform With the inferior platform as the server, in case of any abnormal connection of the subordinate link, the subordinate link initiates to send a message to close the main-subordinate link connection to the superior platform and records it in the log, and then the inferior platform interrupts the connection between the main and subordinate links. 4.3.1.4 Connection and hold request of the subordinate link from superior platform to inferior platform 4.3.1.4.1 Connection request process of subordinate link for superior platform Connection request process of the subordinate link for the superior platform shall comply with the following requirements: a) After the inferior platform successfully logs in the superior platform and the main link is established, the superior platform, by obtaining information such as TCP service IP address and port No. provided by the inferior platform, initiates a connection request of the subordinate link to the inferior platform; b) After the inferior platform receives the connection request of the subordinate link sent from the superior platform, the connection between the subordinate link and the superior platform is immediately established. 4.3.1.4.2 Hold process of subordinate link Hold process of the subordinate link shall comply with the following requirements: a) After successful connection of the subordinate link, in case of any application service data package transmission between the superior platform and the inferior platform, hold data package of the subordinate link needs not be sent; otherwise, the inferior platform shall send one hold request data package of the subordinate link to the superior platform every 1min so as to keep connection of the subordinate link; b) If there is without application data package transmission between the inferior platform and the superior platform, and the inferior platform fails to receive the hold acknowledge data package of the subordinate link sent from the superior platform for consecutive 3min, it shall be considered that its connection with the superior platform have been lost and it will initiate to interrupt the subordinate link of data transmission; c) If there is without application data package transmission between the superior platform and the inferior platform, and the superior platform fails to receive the hold acknowledge data package of the subordinate link sent from the inferior platform for consecutive 3min, it shall be considered that its connection with the inferior platform have been lost and it will initiate to interrupt the subordinate link of data transmission. 4.3.1.5 Log-out request of main link from superior platform to inferior platform When the inferior platform initiates to exit, it will firstly send a log-out request of the subordinate link. After the inferior platform receives it, it will return to the link, log out the response and record it in the log. Then the superior platform will interrupt the subordinate link. 4.3.1.6 Superior platform's initiative closure of the main-subordinate link connection with the inferior platform With the superior platform as the server, in case of any abnormal connection of the main link, the main link initiates to send a message to close the main-subordinate link connection to the superior platform and records it in the log, and then the superior platform interrupts the connection between the main and subordinate links. 4.3.2 Information statistics service process The reception of notification on the amount of the positioning information shall comply with the following requirements: a) The superior platform will receive the amount of vehicle's positioning information, periodically conduct statistics on it and periodically notify the statistical data to the inferior platform; b) The superior and inferior platforms shall receive vehicle's positioning information and check its amount according to the data. 4.3.3 Exchange service process of the vehicle's dynamic information 4.3.3.1 Uploading of the vehicle's registration information from inferior platform to superior platform The inferior platform shall upload the vehicle's registration information after it receives the vehicle's terminal authentication information each time. 4.3.3.2 Real-time uploading of the vehicle's positioning information from inferior platform to superior platform The inferior platform shall upload the vehicle's registration information in real time after it receives the vehicle's positioning information. 4.3.3.3 Real-time exchange of the vehicle's positioning information from superior platform to inferior platform Before the superior platform exchanges the vehicle's positioning information with the inferior platform, it sends the request to start the exchange of the vehicle's positioning information. After the inferior platform receives and responds to the request, the superior platform starts the real-time exchange of vehicle's positioning information with the inferior platform. The request to start exchange of the vehicle's positioning information from the superior platform to the inferior platform shall include the following conditions: a) When the superior platform analyzes the geographic area of non-attribution area with any vehicle entry, it shall inform the inferior platform of the non-attribution area of the entry. b) When the superior platform manually designates the vehicle's positioning information to be exchanged to the designated inferior platform, it shall notify the inferior platform that the vehicle's positioning information shall be exchanged to the superior platform; c) When the superior platform monitors and manages certain vehicle in emergency state, it shall send the uploaded vehicle's positioning information to the inferior platform to which the vehicle is attributed and send the command to the inferior platform. When the superior platform ends up sending vehicle's positioning information to the inferior platform, the exchange shall comply with the following requirements: a) When the vehicle entering the geographic area of the non-attribution area leaves the geographic area, the superior platform shall send the request to end up the exchange of vehicle's positioning information to the inferior platform and notify it to stop the data exchange; b) When the superior platform itself cancels exchanging of the designated vehicle's positioning information to the designated inferior platform, it shall send the request to end up the exchange of the vehicle's positioning information to the inferior platform and cancel the exchange; c) When the superior platform completes the vehicle monitoring and management in emergency, it shall send the request to end up the exchange of the vehicle's positioning information to the inferior platform to which the vehicle is attributed and no longer send the vehicle's positioning information to the above inferior platform. 4.3.3.4 Supplementary report of the vehicle's positioning information from inferior platform to superior platform If the main and subordinate communication links between the superior and inferior platforms are interrupted, the vehicle's positioning information during the interruption shall be supplemented after the recovery of the communication between the main and subordinate links. The supplementary report process of the vehicle's positioning information from the inferior platform to the superior platform shall comply with the following requirements: a) When the inferior platform link is interrupted with the superior platform link during the uploading of the positioning data to the superior platform, the interruption time shall be recorded (if without interaction of application service data package between the two platforms, the receipt time of the hold acknowledge data package of the last subordinate link from the superior platform shall prevail; otherwise, the last receipt time of complete interaction of application service data package with the superior platform prevails); b) After the inferior platform log in again, vehicle's positioning information received during the interruption is automatically sent to the superior platform according to the interruption time. 4.3.3.5 Supplementary sending of the vehicle's positioning information from superior platform to inferior platform If the main and subordinate communication links between the superior and inferior platforms are interrupted, the vehicle's positioning information during the interruption shall be supplemented to send after the recovery of the communication between the main and subordinate links. The supplementary sending process of the vehicle's positioning information from the superior platform to the inferior platform shall comply with the following requirements: a) When the inferior platform link is interrupted with the superior platform link during the exchanging of the data to the superior platform, the interruption time shall be recorded (if without interaction of application service data package between the two platforms, the receipt time of the hold acknowledge data package of the last subordinate link from the superior platform shall prevail; otherwise, the last receipt time of complete interaction of application service data package with the superior platform prevails); b) After the main and subordinate communication links are established again, the inferior platform sends the request for supplementary sending of the vehicle's positioning information according to the recorded platform interruption time; c) After the superior platform receives and responses to the request for supplementary sending of the vehicle's positioning information, it carries out the supplementary sending process of the vehicle's positioning information according to the requirements of Article 4.5.3.2.3.

Foreword I 1 Scope 2 Normative References 3 Terms, Definitions and Abbreviations 4 Technical Requirements 5 Constant Definition