Digi WAN 3G User Manual page 64

Network services settings
The Network Services page shows a set of common network services that are available for Digi
devices, and the network port on which the service is running.
Common network services can be enabled and disabled, and the TCP port on which the network
service listens can be configured. Disabling services may be done for security purposes. That is,
certain services can be disabled so the device runs only those services specifically needed. To
improve device security, non-secure services such as Telnet can be disabled.
It is usually best to use the default network port numbers for these services because they are well
known by most applications.
Several services have a setting for whether TCP keep-alives will be sent for the network services.
TCP keep-alives can be configured in more detail on the Advanced Network Settings page.
Exercise caution in enabling and disabling network services, particularly
Caution
disabling them. Changing certain settings can render a Digi Connect device
inaccessible. For example, disabling Advanced Digi Discovery Protocol
(ADDP) prevents the device from being discovered on a network, even if it is
actually connected. Disabling HTTP and HTTPS disables access to the web
interface. Disabling basic services such as Telnet, Rlogin, etc. can make the
Command-Line interface inaccessible.
Supported network services and their default network port numbers
In Digi devices that have multiple serial ports, the network port number defaults for various
services are set based on the following formula:
base network port number + serial port number
For example, the Telnet Passthrough service is set to network port 2001 for serial port 1, 2002 for
serial port 2, 2003 for serial port 3, etc.
If a network port is changed for a particular service, that is the only network port number that
changes. That change does not carry over to the other network ports. For example, if the network
port number for Telnet Passthrough is changed from 2001 to 3001, that does not mean that the
other network ports will change to 3002, 3003, etc.
There are two types of network services available:
Basic services, which are accessed by connecting to a particular well-known network

port.
Passthrough services, in which a particular serial port is set up for a particular type of

service. To use the service, users must both use the correct protocol and specify the
correct network port. For example, assuming default service ports and using a Linux
host, here is how a user would access the SSH and Telnet passthrough services:
#> ssh -l fred digi16 -p 2501
#> telnet digi16 2101
C o n f i g u r e D i g i d e v i c e s
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