Digi WAN 3G User manual

Digi Cellular Family
User’s Guide
Digi Cellular Family Products
Connect WAN Family:
Digi Connect®WAN
Digi Connect WAN GPRS
Digi Connect WAN GSM-R
Digi Connect WAN VPN
Digi Connect WAN IA
Digi Connect WAN 3G
Digi Connect WAN 3G IA
ConnectPort™WAN Family:
ConnectPort WAN VPN
ConnectPort WAN Wi
ConnectPort WAN GPS
90000753_E

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©Digi International Inc. 2010. All Rights Reserved.
The Digi logo, Digi Connect, iDigi, ConnectPort, Digi SureLink, Digi Dialserv are trademarks or
registered trademarks of Digi International, Inc.
All other trademarks mentioned in this document are the property of their respective owners.
Information in this document is subject to change without notice and does not represent a
commitment on the part of Digi International.
Digi provides this document “as is,” without warranty of any kind, either expressed or implied,
including, but not limited to, the implied warranties of fitness or merchantability for a particular
purpose. Digi may make improvements and/or changes in this manual or in the product(s) and/or
the program(s) described in this manual at any time.
This product could include technical inaccuracies or typographical errors. Changes are periodically
made to the information herein; these changes may be incorporated in new editions of the
publication.

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Contents
Contents........................................................................................................................................................................................3
About this guide...........................................................................................................................................................................6
Purpose................................................................................................................................................................................6
Audience..............................................................................................................................................................................6
Scope...................................................................................................................................................................................6
Where to find more information..........................................................................................................................................6
Digi contact information .....................................................................................................................................................7
Chapter 1: Introduction............................................................................................................................................................8
Important Safety Information..............................................................................................................................................8
Digi Cellular Family products.............................................................................................................................................9
Digi Connect™ WAN...............................................................................................................................................9
Digi Connect™ WAN VPN......................................................................................................................................9
Digi Connect™ WAN IA
Digi Connect WAN 3G IA......................................................................................................................................10
Digi Connect WAN 3G...........................................................................................................................................10
ConnectPort™ WAN VPN .....................................................................................................................................11
Wireless carrier certifications............................................................................................................................................11
Features .............................................................................................................................................................................12
User interfaces.........................................................................................................................................................12
Quick reference for configuring features ................................................................................................................13
Hardware features ...................................................................................................................................................18
Network interface features ......................................................................................................................................18
Configurable network services................................................................................................................................18
IP protocol support..................................................................................................................................................19
Mobile/Cellular features and protocol support........................................................................................................23
RealPort software....................................................................................................................................................24
Alarms.....................................................................................................................................................................24
Modem emulation ...................................................................................................................................................25
Security features......................................................................................................................................................25
Configuration management.....................................................................................................................................26
Customization capabilities ......................................................................................................................................26
Supported connections and data paths in Digi devices .....................................................................................................27
Interfaces for configuring, monitoring, and administering Digi devices ..........................................................................30
Configuration capabilities .......................................................................................................................................30
Configuration interfaces..........................................................................................................................................30
Monitoring capabilities and interfaces....................................................................................................................36
Device administration .............................................................................................................................................37

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Chapter 2: Configure Digi devices.........................................................................................................................................38
Default IP address and methods for assigning an IP address............................................................................................39
Configure an IP address using DHCP.....................................................................................................................39
Configure an IP address using Auto-IP...................................................................................................................39
Configure an IP address from the command-line interface.....................................................................................40
IP addresses and the iDigi Platform........................................................................................................................40
Test the IP address configuration............................................................................................................................40
Configuration through the iDigi Platform.........................................................................................................................41
Create an Account on iDigi.com.............................................................................................................................41
Add the Digi device to the idigi.com Device List...................................................................................................42
iDigi Platform views for configuring and managing Digi devices .........................................................................44
Configuration through the web interface..........................................................................................................................47
Open the web interface............................................................................................................................................47
Organization of the web interface...........................................................................................................................49
Change the IP address from the web interface, as needed ......................................................................................52
Network configuration settings...............................................................................................................................53
Mobile (cellular) settings ........................................................................................................................................97
Serial port settings................................................................................................................................................110
Camera settings .....................................................................................................................................................119
Alarms...................................................................................................................................................................121
System settings......................................................................................................................................................125
Remote management settings................................................................................................................................131
Security settings ....................................................................................................................................................136
Position (GPS support)..........................................................................................................................................140
Applications ..........................................................................................................................................................142
Configuration through the command line .......................................................................................................................147
Access the command line......................................................................................................................................147
Verify device support of commands .....................................................................................................................147
Configuration through Simple Network Management Protocol (SNMP).......................................................................150
Batch capabilities for configuring multiple devices........................................................................................................150
Chapter 3: Monitor and manage Digi devices....................................................................................................................151
Monitoring capabilities from the iDigi Platform.............................................................................................................152
Monitoring capabilities in the web interface...................................................................................................................153
Display system information ..................................................................................................................................153
Manage connections and services.........................................................................................................................168
Monitoring capabilities from the command line.............................................................................................................171
Commands for displaying device information and statistics ................................................................................171
Commands for managing connections and sessions .............................................................................................173
Monitoring Capabilities from SNMP..............................................................................................................................174

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Chapter 4: Digi device administration ................................................................................................................................175
Administration from the web interface ...........................................................................................................................175
File management ...................................................................................................................................................176
X.509 Certificate/Key Management .....................................................................................................................177
Backup/restore device configurations...................................................................................................................180
Update firmware and Boot/POST Code................................................................................................................181
Restore a device configuration to factory defaults................................................................................................182
Display system information ..................................................................................................................................184
Reboot the Digi device..........................................................................................................................................184
Enable/disable access to network services............................................................................................................184
Administration from the command-line interface...........................................................................................................185
Chapter 5: Specifications and certifications .......................................................................................................................186
Hardware specifications ..................................................................................................................................................187
Digi Connect WAN product specifications...........................................................................................................187
ConnectPort WAN product specifications............................................................................................................189
Digi Connect WAN 3G specifications..................................................................................................................190
Digi Connect WAN 3G IA specifications.............................................................................................................191
Wireless networking features..........................................................................................................................................192
Regulatory information and certifications.......................................................................................................................194
RF exposure statement ..........................................................................................................................................194
FCC certifications and regulatory information (USA only)..................................................................................194
Industry Canada (IC) certifications.......................................................................................................................195
Safety statements...................................................................................................................................................196
International EMC (Electromagnetic Emissions/Immunity/Safety) standards.....................................................198
Chapter 6: Troubleshooting.................................................................................................................................................199
Troubleshooting Resources.............................................................................................................................................199
System status LEDs.........................................................................................................................................................200
Connect WAN Family LEDs and buttons.............................................................................................................200
ConnectPort WAN Family LEDs and buttons......................................................................................................203
Glossary....................................................................................................................................................................................205

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About this guide
Purpose
This guide describes and shows how to provision, configure, monitor, and administer Digi devices.
Audience
This guide is intended for those responsible for setting up Digi devices. It assumes some
familiarity with networking concepts and protocols. A glossary is provided with definitions for
networking terms and features discussed in the content.
Scope
This guide focuses on configuration, monitoring, and administration of Digi devices. It does not
cover hardware details beyond a certain level, application development, or customization of Digi
devices.
Where to find more information
In addition to this guide, find additional product and feature information in the these documents:
Online help and tutorials in the web interface for the Digi device
Quick Start Guides
RealPort®Installation Guide
Cellular 101 Tutorial
Digi Connect Family Customization and Integration Guide
iDigi tutorials and user’s guides
Release Notes
Cabling Guides
Product information available on the Digi website, www.digi.com, and Digi's support
site at www.digi.com/support, including, Support Forums, Knowledge Base, Data
sheets/product briefs, application/solution guides, and carrier-specific documents
Python developer Wiki

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Digi contact information
For more information about Digi products, or for customer service and technical support, contact
Digi International.
To Contact Digi International
by: Use:
Mail Digi International
11001 Bren Road East
Minnetonka, MN 55343
U.S.A.
World Wide Web: http://www.digi.com/support/
email http://www.digi.com/contactus/email.jsp/
Telephone (U.S.) [phone] or [phone]
Telephone (other locations) [phone] or [phone]

Introduction
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Introduction
CHAPTER 1
This chapter introduces Digi devices and their product families, types of connections and data
paths in which Digi devices can be used, and the interface options available for configuring,
monitoring, and administering Digi devices.
Important Safety Information
To avoid contact with electrical current:
Never install electrical wiring during an electrical storm.
Never install an Ethernet connection in wet locations unless that connector is
specifically designed for wet locations.
Use caution when installing or modifying lines.
Use a screwdriver and other tools with insulated handles.
Wear safety glasses or goggles.
Do not place Ethernet wiring or connections in any conduit, outlet or junction box
containing electrical wiring.
Installation of inside wire may bring you close to electrical wire, conduit, terminals and
other electrical facilities. Extreme caution must be used to avoid electrical shock from
such facilities. Avoid contact with all such facilities.
Ethernet wiring must be at least 6 feet from bare power wiring or lightning rods and
associated wires, and at least 6 inches from other wire (antenna wires, doorbell wires,
wires from transformers to neon signs), steam or hot water pipes, and heating ducts.
Do not place an Ethernet connection where it would allow a person to use an Ethernet
device while in a bathtub, shower, swimming pool, or similar hazardous location.
Protectors and grounding wire placed by the service provider must not be connected to,
removed, or modified by the customer.
Do not touch uninsulated Ethernet wiring if lightning is likely!
External Wiring: Any external communications wiring installed needs to be constructed
to all relevant electrical codes. In the United States this is the National Electrical Code
Article 800. Contact a licensed electrician for details.

Introduction
9
Digi Cellular Family products
In the Digi Cellular Family, there are two groups of products: Digi Connect WAN products and
ConnectPort WAN products.
Digi Connect™ WAN
Digi Connect WAN is a wireless WAN gateway. It provides high-performance Ethernet-to-wireless
communications through cellular GSM (Global System for Mobile communication) or CDMA
(Code Division Multiple Access) networks for primary and backup connectivity to remote
locations. It uses General Packet Radio Service (GPRS)/Enhanced Data Rates for GSM Evolution
(EDGE) to offer an easy and cost-effective means of connecting virtually any remote location into
the corporate IP network. It is ideal for use where wired networks (for example, leased line/frame
relay, CSU/DSU, fractional T1) are not feasible or where alternative network connections are
required.
Benefits of wireless communications through Digi Connect WAN include instant deployment,
elimination of wiring costs and problems due to wire breaks, the ability to traverse firewalls, and
the ability to move the connection virtually anywhere.
Digi Connect™ WAN VPN
The Digi Connect WAN VPN (Virtual Private Network) is a small cellular-enabled router that
securely connects remote subnets using the Encapsulating Security Payload (ESP) version of IPsec
(IP security) VPN technology. IPsec ESP uses IP protocol 50 and requires each VPN endpoint be
able to reach the other, which usually means each end has a public IP address. Authentication
Header (AH) is not currently supported.
The Digi Connect WAN VPN handles the routing between networks. Devices within the Digi
Connect WAN VPN’s private network can connect directly to devices on the other private network
with which the VPN tunnel is established. Configuring VPN tunnels using security settings and
methods ensures that the networks are secure.
The Digi Connect WAN VPN is based on the same feature set as Digi Connect WAN, plus VPN
capability.

Introduction
10
Digi Connect™ WAN IA
Digi Connect WAN 3G IA
Digi Connect WAN IA is a full-featured serial-to-cellular or Ethernet-to-cellular router designed
for Industrial Automation applications. It features a DIN rail mount kit, terminal blocks for 9-30
VDC power input, Modbus to Modbus TCP conversion support, Class 1, Division 2 certification
and hardened temperature specifications.
Digi Connect WAN 3G IA is an industrial-grade 2.5 to 3G Wireless WAN GSM/GPRS/EDGE/
HSUPA, CDMA/EV-DO router/gateway.
These products offer all of the all of the functionality of the Digi Connect WAN VPN plus an
industrial-grade feature set, including a Modbus bridge for multi-master access and mixing of
protocols such as Modbus/TCP, Modbus/UDP, Modbus/RTU, and Modbus/ASCII. ModbusPlus
requires dedicated hardware and is not supported.
These products provide an alternative to traditional wired TCP/IP Wide Area Networks (WANs),
using global wireless Cellular, and IPSec VPN technology to create secure primary and backup
network connectivity. It offers an easy, cost-effective means of securely connecting virtually any
remote location or device into the corporate IP network.
The Modbus Bridge functionality enables remote Masters to connect through both the Cellular IP
network and the local Ethernet. It supports these protocols:
Modbus/TCP transported by TCP/IP or UDP/IP
Modbus/RTU transported by serial, TCP/IP, or UDP/IP
Modbus/ASCII transported by serial, TCP/IP, or UDP/IP
The factory default settings for these products provide you with a base configuration for Industrial
Automation that you can modify from the device’s Telnet command-line interface. These factory
defaults should be sufficient for most Industrial Automation applications. Should you need to
change the settings from the factory defaults, use the “set ia” command, described in the Digi
Connect Family Command Reference. By default, these products use a a specialized set of serial
port configuration settings for Industrial Automation, or port profile, that you can associate with
serial ports during device configuration (See "About port profiles" on page 110).
For more details on the Modbus Bridge, see the Digi document Remote Cellular TCP/IP Access to
Modbus Ethernet and Serial Devices, P/N 90000773.
Digi Connect WAN 3G
Digi Connect WAN 3G is a 3G high-speed upgradeable HSUPA/EV-DO Rev A Wireless WAN
cellular router with integrated VPN. It provides primary and backup connectivity to remote sites
and devices.

Introduction
11
ConnectPort™ WAN VPN
ConnectPort WAN VPN is a hardened, upgradeable 3G cellular router that provides secure high-
speed wireless connectivity to remote sites and devices. It can be used for primary wireless
broadband network connectivity to equipment at remote locations, as well as for a backup to
existing landline communications. The ConnectPort WAN VPN is ideal for use where wired
networks (for example, leased line/frame relay, ISDN, DSL) are not feasible, or where alternative
network connections are required.
The flexible design of the ConnectPort WAN VPN ensures easy upgrading through supported Type
2 PCMCIA Card slots or PCI Express modules. With an upgradeable wireless network platform,
you can quickly migrate to future 3G platforms and beyond. ConnectPort WAN VPN also includes
two RS-232 serial ports for connecting legacy COM devices and a built-in four-port 10/100
Ethernet switch for connecting additional TCP/IP network devices.
Benefits of the ConnectPort WAN VPN include instant deployment, elimination of wiring costs,
elimination of problems due to wire breaks, and the flexibility to move the connection virtually
anywhere.
Applications include utilities, industrial automation, POS/retail, financial (ATMs), traffic, medical,
video surveillance and more. For applications requiring secure connections, ConnectPort WAN
VPN offers an available integrated IPsec VPN client/server for true end to end data protection.
Wireless carrier certifications
Digi devices are being certified around the world with major carriers supporting these
technologies. For a current list of carrier certifications for your Digi product, go to digi.com and go
the product pages for your product. Click the Specs tab of the product pages. Carrier certifications
are listed under Mobile Certifications or Carrier Certifications.

Introduction
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Features
This is an overview of key features in Digi devices. Software features are covered in more detail in
the next three chapters. Hardware specifications and are covered in Chapter 5, "Specifications and
certifications".
User interfaces
There are several user interfaces for configuring and monitoring Digi devices, including the
following. Some of these user interfaces can be customized.
The iDigi Platform

A web-based interface for configuring, monitoring, and administering Digi devices. For
Digi devices that ship with a default IP address, simply connecting a laptop computer to
the Ethernet port of these products allows direct access to the web interface for
configuration.
A command-line interface available via local serial port, telnet or SSH.
Simple Network Management Protocol (SNMP).

Introduction
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Quick reference for configuring features
This guide primarily focuses on configuring, monitoring, and administering Digi devices from the
web interface. This table provides a quick reference for configuring features and performing
device tasks, and where to find the features and settings in the web interface and this guide. Click
the page number in the Page column to jump to instructions on configuring or using the feature.
Some features are configurable from the command line interface only. In those cases, the
commands that configure the feature are noted. The command descriptions are in the Digi Connect
Family Command Reference.
Feature/task Path to feature in the web interface See page
Administration/Configuration management:
File management: uploading and
downloading files, such as applet
files, and custom splash screens.
Administration > File Management
See also theDigi Connect Family Customization and Integration Guide for
information on uploading and downloading files used to customized a Digi
device’s look-and-feel.
176
Python program file
management. Applications > Python 142
Backup/restore a configuration
from a TFTP server on the
network
Administration > Backup/Restore 180
Update firmware Administration > Update Firmware 181
Reset configuration to factory
defaults Administration > Factory Default Settings 182
System information, including
device identifiers and statistics Administration > System Information 184
Reboot the Digi device Administration > Reboot 184
Certificate and key management,
including X.509, VPN, SSL,
SSH
Administration > X.509 Certificate and Key Management 177
Alarms Configuration > Alarms 121
Autoconnection: automatically
connect a user to a server or network
device
Configuration > Serial Ports> port > Profile Settings > TCP Sockets >
Automatically establish TCP connections 112
Connection management:
Manage serial port connections Management > Serial Ports 168

Introduction
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Manage Virtual Private Network
(VPN) connections Management> Connections>Virtual PrivateNetwork(VPN)Settings 168
Manage active system
connections Management > Connections > Active System Connections 168
Manage network services Management > Network Services
(Currently only DHCP server settings managed from here) 169
Domain Name System (DNS):
DNS Client Configuration > Network > Advanced Network Settings 92
Dynamic DNS (DDNS) update Configuration > Network > Dynamic DNS Update Settings 67
Dynamic Host Configuration Protocol
(DHCP) server To configure a DHCP server: Configuration > Network > DHCP Server Settings
To start and stop and show status of a DHCP server:
Management > Network Services > DHCP Server Management
60
Ethernet settings Configuration > Network > Advanced Network Settings 92
Event logging for the Digi device Management > Event Logging 168
Help on configuring features Help button on each page.
Host name for a device Configuration > Network > Advanced Network Settings > Host Name 92
Industrial Automation (IA) Configuration > Serial Ports > Select Port Profile > Industrial
Automation
The Industrial Automation port profile should address most configuration
scenarios.Tofine-tune yourIA settings, usethe “setia” command fromthe
command line. See the set ia command description in the Digi Connect
Family Command Reference.
For additional information on configuring Industrial Automation, see this
web site:
http://www.digi.com/support/ia
146
IP address settings Configuration > Network > IP Settings
Configuration > Network > Advanced Settings 39, 55, 60, 92
IP filtering / access control Configuration > Network > IP Filtering Settings 70
IP forwarding: Network Address
Translation (NAT) and port
forwarding configuration/static routes
Configuration > Network > IP Forwarding Settings 71
IP pass-through Configuration > Network > IP Pass-through 79
Feature/task Path to feature in the web interface See page

Introduction
15
Mobile (cellular) settings:
Provisioning the cellular
modules Configuration > Mobile
ForDigiCellular productthathave acellularmodule,provisioning mustbe
performed once.
To launch a wizard for provisioning the module, go to
Configuration > Mobile. Under Mobile Service Provider Settings, click
the Provision Device button.
Provisioning can also be performed from the command line:
To provision the CDMA module: provision
To display existing provisioning parameters: display provisioning
99
Mobile service provider and
connection settings Configuration > Mobile
Settings displayed vary by mobile service provider. 98, 105
SureLink™ Settings Configuration > Mobile > SureLink Settings.105
Modem emulation Configuration > Serial Ports > Port Profile Settings >
Modem Emulation
See the Connect Family Command Reference for modem emulation
commands.
114
Port logging: enabling port buffering
and displaying contents of a port
buffer
To enable port logging:
Configuration > Serial Ports > Advanced Serial Settings
To display the contents of a port buffer:
Management > Serial Ports > Port Logs
116
Port profiles: sets of preconfigured
serial-port settings for a particular
connection and use scenario
Configuration > Serial Ports > Port Profile Settings 110
Python support: loading and running
custom programs authored in the
Python programming language.
Applications > Python
For more information on writing and running Python programs, see the
Digi Python Programming Guide.
142
RealPort (COM port redirection)
configuration Configuration > Serial Ports > port > Port Profile Settings > RealPort
See also the RealPort Installation Guide.111
Remote device management Configuration > Remote Management 131
Reverting configuration settings Administration > Factory Default Settings 182
Feature/task Path to feature in the web interface See page

Introduction
16
Security/access control features:
Control access to inbound ports Configuration > Serial Ports > port > Port Profile Settings >
TCP Sockets or UDP Sockets or Custom port profile 110
Secure Shell Server (SSH) Configuration > Security > Enable SSH public key authentication
Network > Network Services > Enable Secure Shell Server (SSH) 139, 65
Establish/change user name for a
user Configuration > Security 136
Issue a new/changed password to
a user Configuration > Security 136
Serial port configuration:
Basic serial port settings Configuration > Serial Ports > Basic Serial Settings 115
Advanced serial port settings Configuration > Serial Ports > Advanced Serial Settings 116
Port profiles: associate a serial
port with a set of preconfigured
port settings for a specific use
Configuration > Serial Ports > Port Profile Settings 110
RCI over serial mode Configuration > Serial Ports > Advanced Serial Settings 116
RTS Toggle Configuration > Serial Ports > Advanced Serial Settings 116
TCP serial connections Configuration > Serial Ports > port > Port Profile Settings >
TCP Sockets port profile 112
UDP serial characteristics Configuration > Serial Ports > port >Port Profile Settings > UDP
Sockets port profile 113
Feature/task Path to feature in the web interface See page

Introduction
17
Simple Network Management Protocol (SNMP):
Configure SNMP through the
web interface Configuration > System > Simple Network Management Protocol
(SNMP) Settings 128
Enable/disable SNMP service Configuration > Network > Network Services 64
Enable/disable SNMP alarm
traps Configuration > Alarms > alarm > Send SNMP trap to following
destination when alarm occurs 123, 124
Use SNMP as primary
configuration interface Basic network and serial settings configurable through standard and Digi-
specific Management Information Blocks (MIBs).
More advanced settings must be set through the web or command-line user
interfaces, and sending alarms as SNMP traps must be configured through
the web interface, on the pages listed above.
35, 150
System information: assign system-
identifying information to a device Configuration > System > Device Identity Settings 125
Socket Tunnel Settings Configuration > Network > Socket Tunnel Settings 78
Statistics for Digi devices Administration > System Information 153
Status of Digi devices Management > Serial Ports, Connections, Network Services 168
VPN (Virtual Private Network) To configure VPN:
Configuration > Network > Virtual Private Network (VPN) Settings
To manage VPN:
Management > Connections > Virtual Private Network (VPN)
Connections
79
Wi-Fi (wireless LAN) devices:
Wireless LAN Settings Configuration > Network > WiFi LAN Settings 56
Wireless Security Settings Configuration > Network > WiFi Security Settings 57
Wireless 802.1x Authentication
Settings Configuration > Network > WiFi 802.1x Settings 59
Feature/task Path to feature in the web interface See page

Introduction
18
Hardware features
A summary of hardware features, including power-supply information, is in "Hardware
specifications" on page 187.
Network interface features
A detailed list of network interface features is in Chapter 5, "Specifications and certifications". See
also the data sheet for your Digi product.
Configurable network services
Access to network services can be enabled and disabled. This means that a device’s use of network
services can be restricted to those strictly needed by the device. To improve device security, non-
secure services, such as Telnet, can be disabled.
Network services that can be enabled or disabled include:
Advanced Digi Discovery Protocol (ADDP): can enable or disable ADDP, but cannot
change its network port number.
RealPort
Encrypted RealPort
HTTP/HTTPS
Line Printer Daemon (LPD)
Remote Login (rlogin)
Remote Shell (rsh)
Simple Network Management Protocol (SNMP)
Telnet
In the web interface, access to network services is enabled and disabled on the Network Services
page of Network Configuration. For more information, see "Network services settings" on page 64.
In the command-line interface, network services are enabled and disabled through the set service
command. See the Digi Connect Family Command Reference for the set service command
description.

Introduction
19
IP protocol support
All Digi devices include a Robust on-board TCP/IP stack with a built-in web server. Supported
protocols include, unless otherwise noted:
Transmission Control Protocol (TCP)
User Datagram Protocol (UDP)
Dynamic Host Configuration Protocol (DHCP)
Simple Network Management Protocol (SNMP)
Secure Sockets Layer (SSL)/Transport Layer Security (TLS)
Telnet Com Port Control Option (Telnet) including support of RFC 2217 (ability to
control serial port through Telnet). See "Serial data communication over TCP and UDP"
on page 20 for additional information.
Remote Login (rlogin)
Line Printer Daemon (LPD)
HyperText Transfer Protocol (HTTP)/HyperText Transfer Protocol over Secure Socket
Layer (HTTPS)
Simple Mail Transfer Protocol (SMTP)
Internet Control Message Protocol (ICMP)
Internet Group Management Protocol (IGMP)
Address Resolution Protocol (ARP)
Advanced Digi Discovery Protocol (ADDP)
Point to Point Protocol (PPP)
Network Address Translation (NAT)/Port Forwarding
Secure Shell (SSHv2)
Generic Routing Encapsulation (GRE) Passthrough
IPSec Encapsulating Security Payload (ESP) on most models
ESP Passthrough
Following is an overview of some of the services provided by these protocols.

Introduction
20
Serial data communication over TCP and UDP
Digi devices support serial data communication over TCP and UDP. Key features include:
Serial data communication over TCP, also known as autoconnect and tcpserial can
automatically perform the following functions:
– Establish bidirectional TCP connections, known as autoconnections, between the serial
device and a server or other network device. Autoconnections can be made based on
data and or serial hardware signals.
– Control forwarding characteristics based on size, time, and pattern
– Allow incoming raw, Telnet, and SSL/TLS (secure-socket) connections
– Support RFC 2217, an extension of the Telnet protocol
Serial data communication over UDP, also known as udpserial, can automatically
perform the following functions:
– Digi Connect products can automatically send serial data to one or more devices or
systems on the network using UDP sockets. Options for sending data include whether
specific data is on the serial line, a specific time period has elapsed, or after the specified
number of bytes has been received on the serial port.
– Control forwarding characteristics based on size, time, and patterns.
– Support incoming datagrams from multiple destinations.
– Support outgoing datagrams sent to multiple destinations.
TCP/UDP forwarding characteristics.
Extended communication control on TCP/UDP data paths.
–Timeout
–Hangup
– User-configurable Socket ID string (text string identifier on autoconnect only)
Dynamic Host Configuration Protocol (DHCP)
Dynamic Host Configuration Protocol (DHCP) can be used to automatically assign IP addresses,
deliver TCP/IP stack configuration parameters such as the subnet mask and default router, and
provide other configuration information. For further details, see "Configure an IP address using
DHCP" on page 39.
Auto-IP
Auto-IP is a protocol that will automatically assign an IP address from a reserved pool of standard
Auto-IP addresses to the computer on which it is installed. For Digi devices are set to obtain its IP
address automatically from a DHCP server and the DHCP server is unavailable or nonexistent,
Auto-IP will assign the device an IP address. For further details, see "Configure an IP address
using Auto-IP" on page 39.