User`s guide

Introduction
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Supported connections and data paths in Digi devices
Digi devices allow for several kinds of connections and paths for data flow between the Digi
device and other entities. These connections can be grouped into two main categories:
 Network services, in which a remote entity initiates a connection to a Digi device.
 Network/serial clients, in which a Digi device initiates a network connection or opens a
serial port for communication.
This discussion of connections and data paths may be helpful in understanding the effects of
enabling certain features and choosing certain settings when configuring Digi products.
Network services
A network service connection is one in which a remote entity initiates a connection to a Digi
device. There are several categories of network services:
 Network services associated with specific serial ports
 Network services associated with serial ports in general
 Network services associated with the command-line interface (CLI)
Network services associated with specific serial ports
 Reverse Telnet: A telnet connection is made to a Digi device, in which data is passed
transparently between the telnet connection and a named serial port.
 Reverse raw socket: A raw TCP socket connection is made to a Digi device, in which
data is passed transparently between the socket and a named serial port.
 Reverse TLS socket: An encrypted raw TCP socket is made to a Digi device, in which
data is passed transparently to and from a named serial port.
 LPD: A TCP connection is made to a named serial port, in which the Digi device
interprets the LPD protocol and sends a print job out of the serial port.
 Modem emulation, also known as Pseudo-modem (pmodem): A TCP connection is
made to a named serial port, and the connection will be “interpreted” as an incoming
call to the pseudo-modem.