InDTU512 Series OSOS Modem

User Manual

Version V1.1, June 2025

www.inhand.com

The software described in this manual is according to the license agreement, can only be used in accordance with the terms of the agreement.

Copyright Notice

© 2025 InHand Networks All rights reserved.

Trademarks

The InHand logo is a registered trademark of InHand Networks.

All other trademarks or registered trademarks in this manual belong to their respective manufacturers.

Disclaimer

The company reserves the right to change this manual, and the products are subject to subsequent changes without prior notice.We shall not be responsible for any direct, indirect, intentional or unintentional damage or hidden trouble caused by improper installation or use.

1 Introduction

InDTU512 is a wireless data terminal designed according to the requirements of the Automatic Meter Reading System (OSOS) for communication via cellular networks, which can be referred to as the OSOS Modem. InDTU512 enables the master station to access the connected metering devices via the internet, allowing the master station to obtain the operational parameters of the meters at any time and record detailed data. InDTU512 enables the master station to access the connected metering devices via the internet, allowing the master station to obtain the operational parameters of the meters at any time and record detailed traceability information. equipped with various hardware interfaces such as Ethernet port, serial port, digital input, relay output, etc., enabling it to connect to various devices on-site and achieve multiple applications.

2 Packing list

1. Standard Accessories

1. Optional Accessories

3 Panel Introduction and Dimensions

3.1 Introduction to Panels

Front Panel

Lower Panel

3.2 Structural Dimensions

4 Installation

Installation Notes:

1. Power requirements: unregulated 57V to 270 VAC, nominal 230V, instantaneous voltage protection of 6K, Reverse voltage protection.
   
2. Environmental requirements: Operating temperature -20℃～70℃, relative humidity 0%～93%. The surface of the equipment may be high temperature, the installation needs to consider the surrounding environment, should be installed in restricted areas.
   
3. Avoid direct sunlight and stay away from heat sources or areas with strong electromagnetic interference.
   
4. Check for cables and connectors required for installation.
   

4.1 Equipment Installation

The DTU512 supports both wall mounting and DIN rail mounting, and the corresponding mounting method is selected according to the customer's deployment scenario. Fix the corresponding mounting kit to the back panel of the device, and then just fix the device to the wall or DIN rail.

4.2 Indicator Light Descriptions

4.3 SIM Card Installation

Simply press the SIM into the SIM slot as shown:

4.4 Antenna Installation

Gently rotate the movable part of the metal SMA connector by hand until it cannot be rotated (at this time, you can't see the external threads of the antenna cable), don't hold the black rubber sleeve and twist the antenna with force.

4.5 Open Cover Inspection

The DTU512 has an open cover inspection button on the right side panel as shown below:

After pressing the button, the housing of the appliance can be opened,

5 Getting Started

5.1 Access to InDTU512

Connect to the InDTU512 using the following default IP address 192.168.225.1

Default factory password:

Username：admin

Password: admin@123

Step 3: After successful login, you can view the system status of the device, as shown below

5.2 System

5.2.1 Basic Setup

This page shows the system language of the device, the name of the device, and the user can customize its parameters.

The parameters are described below:

5.2.2 System Time

In order to make InDTU512 work better with other devices, it is necessary to accurately configure the system time. The configuration method and steps are as follows:

1. The InDTU512 will automatically get the PC's local time
2. Click "Sync Time" in PC Time to synchronize the device time with the local time of PC.
3. Then click "Apply".

1. In the drop-down box of "Timezone", select the corresponding time zone and check "Auto Daylight Savings Time", or select "Custom" to customize the time zone and fill in "Custom TZ String", i.e., customize the time string.
2. Then click "Apply".

1. Fill in the "Auto Update Time" and "NTP Time Servers" parameters in turn.
2. Then click "Apply".

The NTP server parameters are described below:

5.2.3 Serial Port

Set the parameters of the DTU's own serial port according to the serial port parameters of the terminal equipment connected to the DTU to realize normal communication between the DTU and the terminal equipment.

The serial port parameters are described below:

5.2.4 Admin Access

On this page, you can manage user accounts and passwords. At the same time, you are able to restrict the login methods of the device, including HTTP login, SSH login, and TELNET login. In addition, you can add multiple users to realize multi-user access and management of DTU. You can also set the login timeout.

The user access management parameters are described below:

5.2.5 System Log

When logs are stored locally, you can configure the size of the log file, the number of log files, and the log output level; you can also set the DTU to interface with a remote log server, and the DTU will upload all system logs to the remote log server after the setup is completed.

The syslog parameters are described below:

5.2.6 Config Management

This page is used to manage the configuration of the device, such as: importing and exporting configuration, restoring factory settings, and disabling the hardware reset button.

Config Management page parameter descriptions:

5.2.7 Timed reboot

This page can be used to configure the device to reboot at regular intervals, there is no need for manual operation to restart the device.

Scheduler Parameter Description:

5.2.8 Firmware Upgrade

Click "Browse", select the firmware file you want to upload, after uploading, click "Update" to complete the firmware version upgrade.

5.2.9 Reboot

Click "Reboot" and click "Confirm", the device will reboot immediately.

5.2.10 Logout

Click "Logout" and "Confirm" to log out of your current account.

5.3 Network Setup

5.3.1 Cellular Networks

This page shows the current cellular network configuration information of the DTU. You can configure the cellular network parameters by enabling the "Enable" button.

The cellular network parameters are described below:

Profile: Dialing parameter set, used to configure APN, user name, password and authentication method when dialing from a dedicated NIC. If it is not a private NIC, you usually do not need to modify the configuration here. Up to 10 records can be added to the dialing profile.

5.3.2 Ethernet

InDTU contains an Ethernet interface, click "Network->LAN" to configure the parameters of Ethernet interface, there are two network types of Ethernet interface, i.e. "Static IP" and "Dynamic Address". There are two network types for Ethernet interface, namely "Static IP" and "Dynamic Address", and the configuration methods are as follows.

Configure dynamic address acquisition for the interface (network type selected as DHCP) as shown below:

Dynamic Address Acquisition Parameter Description:

1. LAN

4. Type: Select "Dynamic Address" to configure the interface as a DHCP client and use DHCP to obtain IP address, subnet mask and other information.
5. MAC Address: Physical address of the Ethernet interface, unique, keep the default configuration, no need to change it.
6. MTU: Maximum Transmission Unit, in bytes, default value is 1500
7. Disable Lan0 Port: Disable the interface

Configure the interface with a static IP (network type selected as static IP) as shown below:

Static IP Parameter Description:

1. LAN

6. Type: Select "Static lP" to manually configure the IP address and subnet mask for the Ethernet interface.
7. Mac Address: Physical address of the Ethernet interface, unique, keep the default configuration, no need to change it.
8. IP Address: IP address of the Ethernet interface, customizable
9. Netmask: Subnet mask of the Ethernet interface
10. MTU: Maximum Transmission Unit, in bytes, default value is 150
11. LAN Mode: Interface rate/port's mode

5. Auto Negotiation
6. 100M Full-duplex
7. 100M Half-duplex
8. 10M Full-duplex
9. 10M Half-duplex

1. Disable Lan0 Port: Disable the interface

1. Multi-IP Settings:

3. IP Address: the interface can be configured to have multiple IP addresses
4. Netmask: Subnet mask of Multi-IP
5. Description: interface definition, description

1. GARP

3. Enable: enable/disable GARP
4. Broadcast Count: the number of times an interface sends GARP broadcast messages at one time
5. Broadcast Timeout: After sending a GARP broadcast message, wait for the response time, if no response is received within the timeout period, the broadcast is considered to have failed.

5.3.3 Static Route

Click "Network->Static Route" to add, delete or modify the routing information of the device, and after the modification, the data will be forwarded according to the specified routing information.

Static Route Parameter Description:

5. Destination: the destination IP address/net segment to be reached
6. Netmask: subnet mask of the destination address to be reached
7. Gateway: IP address of the next device the packet will pass through on its way to the destination network
8. Interface: the outgoing interface through which the data reaches the destination network
9. Description：Description of the role of the interface, information

5.4 Services

5.4.1 DHCP services

DHCP adopts the client/server communication mode, in which the client requests the server to assign an address, and the server returns the IP address assigned to the client and related information (such as the lease period), so as to realize the dynamic configuration of IP address and other information. You can set and view the configuration of the DHCP server in the "Services->" page.

Start the dhcp server function on the interface to assign addresses to the downstream devices on that interface:

1. Enable DHCP: Enable DHCP server service, this device acts as a DHCP server

6. IP Pool Starting Address: The starting IP address of the DHCP address pool.
7. IP Pool Ending Address: The terminating IP address of the DHCP address pool.
8. Lease: the release time of the IP address, that is, the assigned IP address will be recovered after the configured release time arrives, and the device needs to re-initiate the DHCP request, which cannot be empty.
9. DNS: IP address of the DNS server assigned to the terminal by default
10. Windows Name Server (WINS): IP address of the WINS server
11. Domain Option: Enable this function to specify the domain name information for the client, which simplifies the host name resolution, unifies the namespace, and facilitates the location of network resources; for example, if the Domain Option configures the domain name to be inhand-router.com, the system will resolve the IP address of host.inhand-router.com when the client accesses the device with the host name, which simplifies the operation of the client and reduces the trouble for the user to enter the complete domain name. -router.com, which simplifies the operation of the client and reduces the trouble of entering the complete domain name.

1. Static DHCP: Some scenarios require fixed IP addresses for some terminals, so you can use the Static DHCP function to bind the MAC of the terminal to the IP in the address pool, and the bound terminal will be assigned a fixed address every time it connects to the network.

5.4.2 DNS services

The Domain Name System (DNS) is a distributed database for TCP/IP applications that provides translation between domain names and IP addresses. With DNS, users can directly use easy-to-remember, meaningful domain names for certain applications, and DNS servers in the network will resolve the domain names to the correct IP addresses. You can set and view the domain name servers in the "Service->DNS" page.

Configure DNS servers to support up to two domain name servers, as shown in the following figure:

DNS parameter settings:

3. Primary DNS: Preferred DNS server
4. Secondary DNS: Alternate DNS server, when the preferred DNS server fails, the device will try to initiate domain name resolution request to the alternate DNS server.
5. Disable local DNS server: Disable local DNS server

5.4.3 Device Manager

Device Manager (hereinafter referred to as DM platform) is a "new-generation" IoT device management cloud platform independently developed and operated by InHand, which enables you to manage and monitor InHand hardware devices conveniently through a visual user interface and easy-to-use process. InHand hardware devices can be quickly integrated and managed with a single click, and cloud deployment can be easily deployed to meet the "use-it-or-lose-it" experience, allowing you to focus on your core business and empowering the development of your enterprise.

Connecting to the InHand Device Manager platform parameters are described below:

7. Enable: Enable/disable device connection to the DM platform
8. Service Type: Docking to Device Manager, i.e. to DM platform.
9. Server: Select the address of the server you want to connect to from the drop-down box
10. Registered Account: The name of the account that has been registered on the cloud platform. 
11. LBS info Upload Interval: LBS info upload interval, legal value 60-86400, unit: sec.
12. Series Info Upload Interval: Info upload interval, legal value 3600-86400, unit: sec.
13. Channel Keeplive: heartbeat interval with the cloud platform, legal value 30-3600, unit: second

5.4.4 SNMP services

Simple Network Management Protocol (SNMP) is a widely used protocol for network management.SNMP is mainly used for the management and monitoring of network devices. It allows network administrators to centrally manage various devices in the network through management workstations.

The SNMP parameters are described below:

2. Enable: enable/disable SNMP service
3. Version: There are several versions of SNMP, the most common being SNMPv1, SNMPv2c, and SNMPv3. The different versions differ in terms of security, functionality, and performance.

3. v1: the earliest version, relatively simple functionality, lower security
4. v2c: enhanced in functionality, but still limited in security
5. v3: provides stronger security, including authentication, encryption and access control features

3. Contact Information: Used to store the contact information of the device, when a network problem occurs, the network administrator can use this contact information to find the personnel responsible for the device for troubleshooting and maintenance.
4. Location Information: Record the physical location of the device information, such as the equipment room where the device is located, cabinet location, etc.
5. Community Management:

3. Community Name: SNMP community ID, the community IDs of the management center and the agent should be consistent
4. Access Limit: Defines the limits of SNMP access to the device, either "Read Only" or "Read-Write".
5. MIB View: The MIB (Management Information Base) view defines the set of MIB objects that can be accessed by the management station.

SNMP Trap is initiated actively by the agent to push the information to the management center. the relevant parameters are described below:

2. Trap SigLevel: Trap signal level, avoid all messages are pushed to NMS, according to the set signal level to be pushed
3. Config SnmpTrap

3. Destination Address: IP address or host name of the network management system (NMS)
4. Security Name: the security identification name of the SNMP Trap message, only devices and NMSs with the same security name can communicate with each other, ensuring that the source and receiver of the Trap message are legitimate.
5. UDP Port: The UDP (User Datagram Protocol) port number used to send SNMP Trap messages.

5.4.5 DTU

The DTU parameters are described below:

2. Enable: Tap to enable the DTU function.
3. DTU Protocol: Transparent, TCP-Server, DC Protocol can be selected.

1. Transparent/TCP-Sever: If Transparent Transmission Device is selected as client, then TCP Server Device is selected as server.

8. Protocol: TCP and UDP protocols are available.
9. Mode: Mode, when selecting DTU Protocol as "Transparent" or "DC Protocol", DTU is in "client" mode, when selecting "TCP-Server", DTU is in "Server" mode. When "TCP-Server" is selected, DTU is in "Server" mode.
10. Frame Interval: Time interval for data sending
11. Serial Buffer Frame: the size of serial buffer set when sending and receiving data from serial port, default is 4K.
12. heartbeat ldle interval: timeout time for heartbeat message, if no reply is received after reaching the set time interval, it is considered that this transmission is timeout.
13. Keepalive Interval: time interval to initiate the next heartbeat message after the heartbeat message times out
14. Keepalive Retry Times: When the TCP heartbeat timeout, the device re-sends the TCP heartbeat and reestablishes the TCP connection after reaching the set number of heartbeat retries.
15. Multi-server policy: can choose polling, parallel

2. parallel: simultaneous de-connection to the center of the destination IP address list
3. polling: first connect to the center at the front of the list, if it is connected, then no longer connect to the back; if it is not connected, then follow the order from the beginning to the end to connect, until a center is connected.

6. Min Reconnect Interval: User-defined minimum reconnect interval. When the device starts to connect, if it does not connect successfully, it will reconnect according to this Min Reconnect Interval. Until the user-defined maximum reconnect interval is reached. Legal value: 1-100000, unit: sec.
7. Max Reconnect Interval: User-defined maximum reconnect interval. After the device starts to connect and the connection time reaches the Max Reconnect Interval, it will connect once every this interval (i.e. user-defined Max Reconnect Interval). Legal value: 1-100000, unit: sec.
8. Source IP: The IP address of the device interface corresponding to the IP selected for the source interface. Generally, users do not need to configure it, and it can be empty.
9. Source Port: General users do not need to choose
10. debug log: click to turn on, after turning on, it will print DTU related logs.
11. Multi Server:

2. Server Address: Customize the IP address of the server to which the device will connect.
3. Server Port: Customize the server port number to which the device will connect.

5.5 Firewall Functions

5.5.1 Basic

The Basic parameters are described below:

5. Default Filter Policy: Settings for the overall handling of network traffic by the device, the default is "Accept", i.e., all traffic is allowed to pass through the device.
6. Block Anonymous WAN Requests(ping): when enabled, block anonymous ping requests from WAN (Wide Area Network, usually Internet).
7. Filter Multicast: Enables filtering of multicast traffic
8. Defend DoS Attack: Enable defense against DoS service attacks
9. Allow DNS Proxy: Allow the device to act as a DNS proxy server

5.5.2 Filtering

You can filter network interface data by configuring a series of matching rules to allow or disallow the passage of specified data streams (such as qualified source IP addresses). You can set the filtering policy for network interface data in the "Filtering" page.

The filter rule parameters are described below:

9. Enable: enable/disable the filter rule
10. Proto: access control protocol, optional TCP, UDP, ICMP, ALL, etc.
11. Source: source address of the ACL rule matching message, empty means any, i.e. all networks.
12. Source Port: source port number, empty means any, which means any source port of TCP/UDP message will match. The source port number can only be specified when the protocol is TCP or UDP.
13. Destination: destination address of the ACL rule matching message, empty means any, i.e. all networks.
14. Destination Port: Destination port number, empty means any, i.e. any destination port of TCP/UDP message matches. Only when the protocol is TCP or UDP can the destination port be specified.
15. Action: Accept/Block message passes
16. Log: When enabled, the system will record logs about access control.
17. Description: describes the ACL rule, making it easy to see at a glance what the ACL is doing

5.5.3 Port Mapping

Port mapping is used to realize that external devices, through specific public network addresses and service ports, can accurately direct access requests to specific ports of specific devices in the internal network, thus enabling external devices to communicate and interact with internal devices, breaking the isolation between the internal network and the external network, and realizing external access to specific ports of specific internal devices.

Port Mapping Parameter Description:

10. Enable: enable/disable port mapping function
11. Proto: protocol type, optional TCP, UDP, TCP&UDP.
12. Source: DTU dial-up port IP
13. Service Port: Service port number
14. Internal Address: IP address of the device at the lower end of the DTU LAN port
15. Internal Port: Internal port number
16. Log: When enabled, it will print the port mapping related logs.
17. External Interface (Optional): Interface number for external device access (Optional)
18. External Address(Optional): restrict the IP address of the external access device, the default is empty, i.e., any address is allowed to access the DTU and the lower end device of the DTU (Optional)
19. Description: description of the port mapping rule, easy to see at a glance the role of the rule

5.5.4 DMZ

The DMZ parameters are described below:

4. Enable: Enable/Disable DMZ
5. DMZ Host: Configure DMZ Host IP
6. Source Address Range: External networks within the source address range can access the DMZ host of the device, but cannot access other internal networks of the DTU; if the source network address is empty, all external networks are allowed to access the DMZ host of the device.
7. Interface: DMZ-related connection interface

5.5.5 MAC-IP Bunding

MAC-IP binding is a network management technology designed to associate and fix the Media Access Control address (MAC address) of a specific device with an Internet Protocol address (IP address), so that only the bound address can access the corresponding network, which enhances network security and facilitates network management. For example:

1, a new MAC-IP binding rules: device LAN port under the end of the PC's MAC address binding IP address 192.168.2.66; 

2, only when the LAN port under the end of the PC's IP address 192.168.2.66, you can normally through the device to access the extranet; 

3, configure the PC's IP address for the address other than the non-192.168.2.66. PC cannot access the external network;

5.5.6 Network Address Translation

Network Address Translation (NAT) enables multiple hosts on a LAN to access the public network through one or more public IP addresses, i.e., using a small number of public IP addresses to represent a large number of private IP addresses, thus saving IP addresses on the public network. You can view and set the NAT rules in the Network Address Translation page.

Network Address Translation Parameter Description:

2. Enable: Enable/Disable Network Address Translation
3. Type

2. SNAT: Source Address Translation, translates the source address of an IP packet into another address. Generally used for data sent from inside the gateway to the outside.
3. DNAT: Destination Address Translation, converts the destination address of an IP packet to another address. Generally used for data sent from outside the gateway to the inside.

10. Proto: the protocol used for network packets, common IP, TCP, UDP, TCP & UDP
11. Source IP: the source IP address to be converted.
12. Source Port: the source port number where the conversion needs to be done
13. Destination: Destination IP address to be converted.
14. Destination Port: Destination port number to be converted.
15. Interface: Convert data to that interface for forwarding
16. Translated Address: Translated IP address
17. Translated Port: Translated port number
18. Log: when turned on, NAT-related log messages will be printed
19. Description: describes this NAT rule

5.6 Tools

Select "Tools" to enter the Tools page. You can diagnose the network problems of DTU in this page. You can enter some extended options in Expert Options, such as: Ping tool in the Expert Options configuration -s 100 that is, send 100 bytes of data packets.

Use the Ping tool to detect whether the network is reachable, as shown below:

Use the route probing tool to determine the path through which IP datagrams access the destination, as shown in the following figure:

Use the network packet capture tool to capture the data transmitted on the specified interface as shown below:

Network Speed Test:

1, click "Browse" to select a file larger than 10M less than 2000M, click "upload" page will return to the upload rate; 

2, click "download", the page will automatically download a test.bin file for testing network download speed. Click "download", the page will automatically download a test.bin file for testing network download speeds

5.7 Status

5.7.1 System Status

This page summarizes the system status of the DTU. In the System Status section you can view information such as the device name, model number, serial number, version information, current time of the device, startup time, CPU performance, storage, and more.

5.7.2 Modem Status

This page outlines the cellular module status of the DTU. In the Modem section you can view SIM card status information, current signal strength, SIM card registration status and more.

5.7.3 Network Connection Status

This page outlines the network connectivity status of the device, such as the interface's IP address, subnet mask, DNS information, and so on.

5.7.4 Routing Table Status

This page summarizes the current routing details of the device, such as the destination network address/segment, the gateway address of the next hop to which the data will be forwarded, and the outgoing interface information, among others.

5.7.5 Device List

This page shows the IP, MAC, and interface information of the devices connected to this DTU unit.

5.7.6 System Logs

You can select "Status> Log" to enter the "Log" page. This page contains a lot of information about the network and DTUs, including operational status, configuration changes, and so on.

5.7.7 Third Party Software Notices

Select "Status->Third Party Software Notices" to enter the Third Party Software Notices page. You can view the third party software notices for IG Software here.