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Remote Wireless Networking 101 - Datasheet Digi International Inc.
Worldwide Headquarters

11001 Bren Road East
Minnetonka, MN 55343
PH: 1-877-912-3444

1-952-912-3444
Email: info@digi.com
Digi International
Regional Office
115 Wild Basin Road
Suite 210
Austin, TX 78746
PH: 1-512-306-0600
Digi International
Regional Office
411 Waverly Oaks Road #304
Waltham, MA 02452
PH: 1-800-243-2333

1-781-647-1234
Digi International GmbH
Joseph-von-Fraunhofer Str. 23
D-44227 Dortmund
Germany
PH: +49-231-9747-0
Digi International
(HK) Limited
Suite 1703-05, 17/F
K Wah Centre
191 Java Road
North Point, Hong Kong
PH: +852-2833-1008
Digi International (HK) Limited - Beijing
Representative Office
Rm 16B12, 16F, Han Wei Plaza
No.7 Guang Hua Road, Chao Yang District
Beijing 100004, China
PH: +86-10-6561-8310
Digi International Denmark
Naverland 2
2600 Glostrup
Denmark
PH: +45-491-770-90
Digi International N.V.
Keizersgracht 62-64
1015 CS Amsterdam
Netherlands
PH: +31-20-5207-566
Digi International (UK) Ltd
Ashwood House, Almondsbury
Business Center Woodlands
Bradley Stoke, Bristol
BS32 4QH
PH: +44(0)1454-643444
Digi International
2 rue de LEglise
92200 Neuilly sur Seine, France
PH: +33-1-55-61-98-98
Digi International KK.
NES Building South 8F.
Sakuragaoka-cho, Shibuya-ku
Tokyo, Japan
PH: +81-3-5428-0261 +
Table of Contents
 Overview

......................................................... pg. 3
1.1 Key Topics ................................................................... pg. 3
1.2 Introduction ................................................................. pg. 3

2 Wireless Data Technology
................................ pg. 4
2.1 Data Offerings ............................................................. pg. 4
2.2 Early Wireless Data Solutions ........................................ pg. 5
2.3 Wireless Data Performance ........................................... pg. 6
2.4 Cost ............................................................................ pg. 7
2.5 IP Considerations for Wireless Networks ........................ pg. 7
2.6 Persistent Connections................................................... pg. 9
2.7 Product Offerings ......................................................... pg. 11
3 Wireless Data Applications
............................... pg. 3
3.1 Primary Network Connection ........................................ pg. 14
3.2 Backup Network Connection ......................................... pg. 14
3.3 VPN Connection........................................................... pg. 15
3.4 Mobile Initiated Application .......................................... pg. 15
3.5 Mobile Terminated Application ...................................... pg. 16

4 Pre-Deployment Considerations
........................ pg. 6
4.1 Security ....................................................................... pg. 16
4.2 Coverage .................................................................... pg. 17
4.3 Antenna Selection ........................................................ pg. 17
5 Complete Wireless Solution
.............................. pg. 9
5.1 Hardware and Distribution ............................................ pg. 19
5.2 Wireless Carriers ......................................................... pg. 19
5.3 Managing Remote Devices ............................................ pg. 19
6 Glossary of Terms
............................................ pg. 2
pg. 2  Overview
The purpose of this document is to provide an overview of remote wireless data
communications over GSM and CDMA networks.
. Key Topics
Introduction to remote wireless data networks
Remote wireless data applications
Remote wireless carrier selection
IP addressing options
Provisioning remote wireless devices
Pre-deployment considerations
Managing remote wireless devices
.2 Introduction
Never before has there been such a compelling reason to connect remote devices.
Customers have been waiting for the right time to make the jump to wireless data
communications, and a series of circumstances have converged to make today the
best time to begin the process of connecting remote devices wirelessly. Why is this
a good time to evaluate wireless solutions?
Wireless data networks are getting faster
Data plan costs have plummeted
Coverage area has increased substantially
Networks have become more reliable
Customers are seizing this opportunity to address challenges they see in business:
Need to differentiate from competition
Need for real-time access to device data
Need to create revenue from service offerings
Need for easy/inexpensive access to data
Digi International is known for making connectivity to devices easy.

We have extended this capability to remote devices using GSM and
CDMA wireless networks. New products such as Digi Connect
®
WAN and
ConnectPort WAN product families break new ground by enabling customers
to have access to virtually any device, anywhere.
pg. 3 2 Wireless Data Technology
2. Data Offerings
The dominant cellular/Personal Communiation Services (PCS) technologies in
North America and worldwide are Global System for Mobile communication
(GSM) and Code Division Multiple Access (CDMA). GSM has the largest
international presence. Cellular and PCS differ primarily in their respective
operational frequency bands. Cellular operates in the 800 MHz frequency band
and PCS operates in the 1900 MHZ frequency band. In Europe and certain Latin
American countries, GSM networks operate in the 900 MHz, 1800 MHz and
2100 MHz (UMTS) frequency bands. Some new CDMA networks in Eastern
Europe and Asia deploy in the 450 MHz band. This document will refer to cellular
and PCS technology collectively as wireless.
Both GSM and CDMA have evolved with technology improvements in what is
called Generations, or G (i.e., 1G, 2G, and 3G), with fractional Generations
recognized for the second Generation (i.e., 2.5G, 2.75G). With each technology
improvement comes higher data rates and network enhancements. Table 1 shows
the evolution path for GSM and CDMA.

HSPDA
1xEV-DV
1xEV-DO
GSM
CDMA
IS-95A
1-2G
2.5G
2.75G
3G
GPRS
CDMA
IS-95B
EDGE
1xRTT
UMTS
pg. 4 2.2 Early Wireless Data Solutions
The first wireless data solutions were circuit switched and worked the same as
dial-up modem to modem communications. These wireless modems operated in the
voice channel, which means throughput was very slow and airtime was expensive.
In addition, wireless modems required an analog (POTS) modem at the opposite
end of the connection.
Although the Digi Connect cellular products are able to emulate a wireless modem,
they actually do much more. They are intelligent gateways with a full TCP/IP stack
and embedded Real-Time Operating System (RTOS) which allow remote devices
and networks to be natively integrated with IP devices and applications across
high-speed digital wireless networks.
Another major difference is that applications can natively connect to remote
devices using TCP/IP without having to use a standard analog modem at one end
and a wireless modem at the other.
Serial Device Connection Using a Standard Wireless Modem
(Modem required at both ends)

Serial Device Connection Using a Digi Connect WAN RG Over an IP Network
(Serial device communicates directly to application server using TCP/IP)
Internet/Frame
Relay
IP WAN
Wireless
Carrier
Application
Server
Digi Connect
®

Cellular Device
Serial
Device
RESET
9-30V D
C
525mA M
AX
STATUS
PWR
ETHERN
ET
ACT
LINK
D

C
RG
AUX
SIGNAL
STRENG
TH
LINK
ACTIVE
SERIAL
Landline
Carrier
Wireless
Carrier
Application
Server
POTS
Modem
Cellular
Modem
Serial
Device
pg. 5 2.3 Wireless Data Performance
As technology has changed from circuit switched networks to packet data, so
has the data throughput performance. Table 2 indicates how these wireless
technologies have improved the peak data rates and to what extent packet data
technology has increased the efficiency of wireless data technology. Early circuit
switched technology, as described in the previous section, required a continuous,
non-shared radio link connection to the wireless network. Packet data networks
provide a more optimal solution by allocating the shared radio link resources only
as needed during packet transmissions.
Table 2
** Same overall performance as class 10 with improved uplink performance.







Connection Theoretical Carrier
Typical


Technology Generation
Type
Max
Max Throughput




Kbps
Kbps
Kbps
GSM
1G
Circuit
----
9.6
----
CDMA
2G
Circuit
----
14.4
----

GSM GPRS
Class 6
2.5G
Packet
64.4
40.6
15-30
GSM GPRS
Class 10
2.5G
Packet
86.2
54.2
20-40

GSM GPRS
Class 12**
2.5G
Packet
86.2
54.2
20-40
CDMA
1xRTT
2.75G
Packet
307
153
60-80
GSM Edge
Class 2
2.75G
Packet
118
118
40-80
GSM Edge
Class 10
2.75G
Packet
237
237
80-160
GSM Edge

Class 12**
2.75G
Packet
237
237
80-160
UMTS

(W-CDMA)
3G
Packet
384
384
200 300
1xEVDO
(CDMA2000)
3G
Packet
> 2000
>2000
400 700
HSDPA
3G
Packet
> 2000
>2000
400 700
pg. 6 Column Definitions
Generation:
Terminology used to broadl