Chapter 3 – Using the Web Management Software
Packet Filters, DNAT Configuration Parameters
DNAT Configuration Group
Destination Network Address Translation (DNAT) allows you to place servers within the protected network and make them available for a certain service to the outside world. The DNAT process running on the router translates the destination address of incoming packets to the address of the real network server on the LAN. The packets are then forwarded.
You can Delete or Edit a DNAT rule after it has been defined and added by using the table at the bottom of the screen.
Note: When adding rules, at least one host must be defined in the Network Configuration section.
Allow Access: Select a network or host to which IP packets are allowed and re-routed. The network/host must be pre-defined in the Network Configuration section.
External Service: Select the External Service that you want allowed. The service must be defined in the Service
Configuration section.
LAN IP: Select the LAN IP to which the packets are to be diverted. Only one host can be defined as the destination.
Internal Service: Select the Internal Service to be the destination.
Internal Source: Select the source address for packets that are going to be sent. If you do not want to change the address, select NOCHANGE.
Save Button: Click Save. The defined DNAT configuration is added and appears at the bottom of the page. Entries can be deleted or edited by clicking the Edit or the Delete buttons.
Example: Setting Up DNAT and Port Forwarding to an Internal Device
Note: The internal device can be camera, meter, security device, and so on.
Situation: Assume the device is on a LAN with an IP address of 192.168.2.100 and the port to access the device is port 7700.
1. In the Network & Services > Network Configuration group, define the following parameters:
Name – Enter a name for the LAN device.
IP Address and Subnet Address – Enter the IP address and subnet address of the device.
Example: Name = MeterIP
IP Address = 192.168.2.100
Subnet Address = 255.255.255.255. The subnet mask in the network configuration is not defined using x.x.x.x notation. It uses ‘bit’ notation. So 255.255.255.255 = 32.
64 MultiModem rCell User Guide
Chapter 3 – Using the Web Management Software
2.
To save this configuration, click Add.
3.
In the Network & Services > Service Configuration group, define a service name. For this example, the service is a meter.
Name – Enter a name for the service (use a name that identifies the service for you). Example: MeterPort
Protocol – Select a protocol. Example: tcp or udp
S-Port / Client – Enter the source port for this service. Example: 1:65535
D-Port / Server – Enter the destination port for this service. Example: 7700
Add – Click the Add button to save this configuration.
4.
In the Packet Filters > DNAT Configuration group, define the DNAT rule.
Allow Access – Select the original target network/host of the IP packets that you now want rerouted. The original target network/host is the one previously defined in the Network Configuration section. Example: Any
External Service – Select the External Service that you want allowed. The service must be defined in the
Service Configuration section.
LAN IP – Select the LAN IP to which the packets are to be diverted. Only one host can be defined as the destination.
Internal Service – Select the Internal Service to be the destination.
Pre DNAT Service – Select the service for the Pre-DNAT destination. This service was just defined in the
Service Configuration section. Example: MeterPort
Post DNAT IP – Select the destination to which the IP packets are to be diverted. Only one host can be defined as the Post DNAT destination. Example: MeterIP
Post DNAT Service – Select the service for the Post DNAT configuration. Example: MeterPort
Internal Source – Select the source address for packets that are going to be sent. If you do not want to change the address, select NOCHANGE. Example: NOCHANGE
5.
To save this configuration, click Save.
Note: You must click Save and Restart once you have completed and submitted all the screens on which you have made changes. The device saves all the settings and reboot the computer.
MultiModem rCell User Guide 65
