Summary of several common problems in GPRS DTU

1、 What is GPRS DTU?

Explanation 1: data transmission takes the CDMA channel

Explanation 2: a terminal for wireless transparent transmission in industry

Explanation 3: DTU (distribution terminal unit) CDMA is the English abbreviation of "code division multiple access" digital wireless communication technology. In short, it means CDMA terminal equipment

2、 Purpose of GPRS DTU?

The emergence of DTU wireless communication terminal meets the requirements of long-distance data transmission and communication, especially for the installation and construction of scattered data acquisition points, remote locations, unattended and wired communication

Inconvenient and high cost industries, such as meteorology, environmental protection, water conservancy, electric power, oil pipeline monitoring, urban pipe network monitoring, industrial monitoring, transportation and POS intelligent retail,

It greatly improves the ability of data communication, saves the cost of human and material resources, and realizes the leap of data communication.

3、 What are the main functions and features of GPRS DTU?

Main functions of DTU:

1. Always online; DTU data terminal can maintain the connection with GPRS / CDMA network, can detect the status of the network in real time, and keep the communication link unblocked;

2. Automatic dialing; When the link between DTU and the network is interrupted due to the shutdown of the network or external power supply, DTU can automatically initiate dialing and re establish the connection with the designated ip of the network.

3. Transparent transmission; The so-called transparent transmission means that after the user data is transmitted through the network, it is output in strict accordance with the original data code when it reaches the serial port, and there is no need for the user to process such as protocol decoding.

4. Standard UDP / TCP data transmission; Users can choose to use the communication protocol according to the characteristics of data. UDP protocol is "unlinked data transmission protocol" and TCP protocol is "reliable data transmission protocol";

When UDP is selected for data transmission, the data usually has the characteristics of reproducibility and the loss of data does not affect the overall situation, such as collecting data for temperature, pressure, flow, GPS position information and so on.

When TCP is selected for data transmission, data is usually required to be complete and indispensable.

5. Fixed IP and support dynamic domain name;

DTU not only supports connection with fixed IP, but also supports dynamic domain name resolution. This feature provides a solution for users without fixed IP to use DTU

4、 Remote meter reading requirements and solutions for GPRS DTU?

Requirements for DTU:

1. DTU is dormant at ordinary times. When DSC needs to copy data, it sends a command to wake up DTU to establish GPRS connection with DSC for data communication.

2. DTU can set two communication channels, namely main DSC and standby DSC. DSC can also set IP or dynamic domain name.

3. DTU needs to support virtual private network (VPN).

4. Wake up DTU by sending SMS to DTU from Feixin's PC customer service terminal. Therefore, DTU needs to recognize the wake-up command sent by Feixin customer service terminal.

5. In our system, there are two DSC. Therefore, the short message configuration channel number of DTU needs to support 2. That is, DTU can recognize the wake-up command sent by Feixin of these two numbers. Specifically, the number of main DSC is a, and the number of standby DSC is B; When a sends the wake-up command, DTU is connected with the main DSC, and when B sends the wake-up command, DTU is connected with the standby DSC. The two cannot conflict.

6. Interactive interface tools shall be used for DTU parameter configuration.

7. There is a tool for managing the connected DTU at DSC.

8. Provide technical documents and development platform of DTU communication protocol for secondary development.

By establishing a TCPIP connection, you can communicate with the center to realize real-time data acquisition

Remote meter reading is not real-time. Generally, UDP mode can be adopted once a month, but each site shall be equipped with data acquisition and transmission device (such as jy-dtu-c or jy-dtu-g)

5、 Can CDMA DTU be connected with configuration software?

DTU can be used directly with configuration software, such as Asian control, force control, Kunlun configuration and so on! Click to download rtu6640v2# force control. Zip and Kingview. Rar

6、 What is the common networking mode of GPRS DTU?

Scheme 1: the central server adopts the fixed IP address of the public network, and jy-dtu-g and jy-dtu-c series GPRS-DTU directly access the Internet host through the IP address.

Scheme 2: the central server adopts dynamic public network IP + dynamic domain name resolution software such as ADSL. Jy-dtu-g and jy-dtu-c series GPRS-DTU resolve the IP address of the central server through DNS to complete two-way communication. This method can greatly save the cost of public network fixed IP,

However, the stability is subject to the stability of DNS server, so we should find a reliable DNS service provider. This scheme is suitable for small-scale applications.

Scheme 3: the central server adopts ADSL and other dynamic public network IP + * * IP resolution server software + GSM modem. After gr100 series GPRS-DTU dials up and goes online, it sends * * information to * * IP resolution server, and * * IP resolution server sends back the host IP address through * * information to complete two-way UDP communication. This method can greatly save the cost of fixed IP in the public network. This scheme is more stable than scheme 2, does not need a stable DNS service provider, and has higher security and stability. If dynamic public network IP such as ADSL is adopted, customers are recommended to use this scheme.

Scheme 4: the center adopts jy-dtu-g and jy-dtu-c series GPRS-DTU or gprs modem, and the whole network adopts mobile APN private network fixed IP.

In this scheme, customers first apply for APN private network service with mobile. Mobile assigns a special APN to customers, and ordinary users are not allowed to apply for the APN. The SIM card used for GPRS private network only opens this special APN, and the use of other APNs is limited. After obtaining the APN, assign mobile internal fixed IP to all monitoring points and centers. However, compared with scheme 2, this scheme does not need DNS resolution. It has mobile intranet fixed IP, reduces intermediate links and enhances stability; All data are transmitted in the APN intranet of mobile gprs without going through the public network, and the security is enhanced. This scheme does not need to bear the monthly rent of the special line. It is cost-effective and recommended.

Scheme 5: the center adopts APN dedicated line, and all points adopt intranet fixed IP. In this scheme, the customer center is connected to the GPRS network of the mobile company through a 2m APN special line, the private fixed IP address is used for wide area connection between the interconnection routers of both parties, and the GRE tunnel is used between GGSN and the interconnection router of the mobile company. Assign a special APN to customers, and ordinary users shall not apply for the APN. The SIM card used for GPRS private network only opens this special APN, and the use of other APNs is limited. After obtaining the APN, assign mobile internal fixed IP to all monitoring points and centers. End to end encryption is adopted between mobile terminal and server platform to avoid possible leakage of information in the whole transmission process. Both parties adopt firewall for isolation, and filter IP address and port on the firewall. The security and stability of this scheme are greatly improved compared with the previous schemes, and it is suitable for the application environment with high security requirements, more data points and high timeliness requirements. The best networking mode when funds allow.