Rajant BreadCrumb ME3 User manual
FCC and IC Statements
This equipment has been tested and found to comply with the limits for a Class A digital device,
pursuant to Part 15 of the CC Rules. These limits are designed to provide reasonable protection
against harmful interference when the device is operated in a commercial environment. This device
generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance
with this instruction manual, may cause harmful interference to radio communications. Operation of
this device in a residential area is likely to cause harmful interference in which case the user will be
required to correct the interference at their own expense.
This Class A digital apparatus complies with Canadian ICES-003 and RSS-210 rules.
Cet appareil numérique de la classe A est conforme à la norme NMB-003 et CNR-210 du Canada.
WARNING: To satisfy CC R exposure requirements a minimum safe distance of 20 cm must be
maintained between this device and all persons while the device is operating.
CAUTION: To reduce potential radio interference to other users, the antenna type and its gain
should be chosen so that the equivalent isotropically radiated power (EIRP) is not more than that
permitted for successful communication.
CAUTION: Changes or modifications not expressly approved by Rajant Corp. could void the user's
authority to operate the equipment.
Copyright Statement
You may use the software provided with the products only on personal computers owned by the
purchasing individual or entity, and may not use, load, or run any such software on any network or in
any type of service bureau, time-sharing operation, or non-purchasing individual or entity's
equipment.
BCAdmin and BCAPI are trademarks; Rajant, the Rajant logo, BreadCrumb, Instamesh, BC|
Commander, and Bring Your Network with You! are registered trademarks of Rajant Corp. in the
United States and certain other countries.
BreadCrumb® ME3 User Guide
Copyright © 2009–2010 Rajant Corp. All rights reserved.
Rajant Corporation BreadCrumb® ME3 User Guide
03-100116-001 Version: 1.02
able of Contents
Preface....................................................................................................................................v
Purpose and Scope.............................................................................................................v
User Information..................................................................................................................v
Related Documentation.......................................................................................................v
1 Introduction.......................................................................................................................1
1.1 What is a BreadCrumb?...............................................................................................1
1.2 Mobility through Meshing.............................................................................................2
1.2.1 Mesh – A Definition...............................................................................................2
1.2.2 BreadCrumbs Mesh by Channel and ESSID.......................................................2
1.3 Description of BreadCrumb ME3.................................................................................3
1.3.1 Radio.....................................................................................................................4
1.3.2 Enclosure..............................................................................................................
1.3.3 18-Pin Amphenol Connector.................................................................................6
1.3.3.1 Power............................................................................................................6
1.3.3.2 Ethernet.........................................................................................................6
1.3.3.3 USB...............................................................................................................7
1.3.4 Antenna Connector...............................................................................................7
1.3. Status LED............................................................................................................7
1.3.6 Zeroize Keys and Restore Factory Defaults / LED Configuration Switch............8
1.3.6.1 Zeroize Keys and Restore Factory Defaults.................................................8
1.3.6.2 LED Configuration.........................................................................................9
1.3.7 Internal Battery...................................................................................................10
2 Using BC|Commander....................................................................................................11
3 Deploying the BreadCrumb Wireless Network............................................................13
3.1 Addressing.................................................................................................................13
3.1.1 BreadCrumb Device Addresses.........................................................................13
3.1.2 DHCP..................................................................................................................13
3.2 Channel Assignments................................................................................................13
3.3 Physical Placement and other Considerations..........................................................14
3.3.1 Line-of-Sight.......................................................................................................14
3.3.2 Distance..............................................................................................................14
3.3.3 Weather..............................................................................................................1
3.3.4 Interference.........................................................................................................1
3.3. Placement of BCWN Components.....................................................................1
3.4 Deployment Guidelines and Methodology.................................................................1
3.4.1 Deployment Guidelines......................................................................................16
3.4.2 Deployment Methodology...................................................................................16
4 BreadCrumb ME3 USB Firmware Upgrade...................................................................19
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5 roubleshooting..............................................................................................................21
.1 Sporadic Network Connectivity..................................................................................21
.2 BreadCrumb Device Cannot Connect to BCWN.......................................................22
Appendix A: Error and Warning Codes..........................................................................A-1
List of Figures
Figure 1: All BreadCrumbs Use the Same ESSID.................................................................3
Figure 2: ESSID of BreadCrumb C Changes to "lonely.".......................................................3
Figure 3: BreadCrumb ME3 Enclosure Features...................................................................
Figure 4: 18-Pin Amphenol Connector...................................................................................6
List of ables
Table 1: ME3 Model versus Radio Frequency.......................................................................4
Table 2: 2.4 GHz Radio Channels and Frequencies..............................................................4
Table 3: 900 MHz Radio Channels and Frequencies............................................................
Table 4: Status LED Color Codes..........................................................................................8
Table : Default and alternate display states of the Status LED............................................9
Table 6: Sporadic Network Connectivity Issues...................................................................21
Table 7: BreadCrumb to BCWN Connectivity Issues...........................................................22
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Preface
Purpose and Scope
This manual provides information and guidance to all personnel who are involved with and use
Rajant Corporation’s BreadCrumb ME3 product.
This manual begins with an introduction to the BreadCrumb Wireless Network (BCWN). It then
characterizes the features of the BreadCrumb ME3. inally, it describes common deployment
scenarios and provides concise step-by-step instructions for each scenario.
User Information
The user of this manual is encouraged to submit comments and recommended changes to improve
this manual. Please send any comments or changes to [email protected]. Be sure to include the
version number of the manual you are using and please provide the page numbers related to your
comments wherever possible.
Related Documentation
or additional BreadCrumb ME3 information, refer to these documents:
•BC|Commander® User Guide: This document contains information on the BC|Commander
management application, which is used to configure BreadCrumbs before or during a
deployment.
•BreadCrumb® Video Guide
•BreadCrumb® VLAN Guide
•Troubleshooting ange User Guide
•F Component Installation and Verification in BreadCrumb® Networks
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1 Introduction
Rajant Corporation's (http://www.rajant.com) BreadCrumb ME3 utilizes the 802.11g wireless
networking standard to form a wireless mesh network. The network is mobile, self-integrating, self-
meshing, self-healing, full-duplex and secure. The focus is on flexibility, adaptability, and
simplicity.
The BreadCrumb Wireless Network (BCWN) is intended for rapid deployment of a broadband
wireless network into a situation or “hot zone.” The network can be deployed as a stand-alone
wireless network, or bridged to another network (such as the Internet) utilizing available reach-back
communication links (such as a DSL, cable, or satellite modem).
BreadCrumb ME3 provides high bandwidth applications to stream video, audio as well as data over
large distances. The network traffic can be secured by using different security features offered by
the BCWN. This makes the network optimal for tactical deployments as well as emergency
response situations since it offers robustness, stability and ease of setup in mission critical activities.
Note Throughout this document, unless otherwise stated, the terms Breadcrumb and ME3
are used to refer to ajant BreadCrumb ME3.
1.1 What is a BreadCrumb?
A BreadCrumb is an IEEE 802.11 (Wi- i) and Ethernet compatible networking device which has the
capacity to connect to other BreadCrumbs or networking devices to form a BreadCrumb network. A
BreadCrumb is specifically designed for the following scenarios:
Temporary Wireless Networks
Networks that must be established quickly and with minimal effort for short-term use (e.g., a
network established to provide irst Responder support at the site of a disaster).
Mobile Wireless Networks
Networks in which the network infrastructure itself is mobile, in addition to client devices (e.g., a
convoy viewing a video stream from a UAV).
Wireless Network Extension
Networks in which a wireless network must be quickly extended around or through obstacles that
block wireless communications (e.g., urban canyon networks, tunnels/caves, etc.)
Wired Network Extension
Networks in which two or more wired LANs at different locations must be connected wirelessly
(e.g., to securely connect combat service support computers with logistics bases)
Any Combination of the Above
Most BreadCrumb deployments include elements from more than one of the above scenarios.
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In many cases, BreadCrumbs will perform all of these tasks as shipped with no configuration
necessary at all, providing an instant TAN (Tactical Area Network). Moreover, because
BreadCrumbs use industry-standard 802.11 communications, client devices such as laptops or
handheld computers require no special hardware, software, or configuration to access a BCWN.
1.2 obility through eshing
The key component to a BCWN is a technique known as meshing. While this is generally handled
automatically by BreadCrumbs, complex deployment scenarios require a basic understanding of how
BreadCrumbs establish and maintain a mesh.
1.2.1 Mesh – A Definition
A mesh is a collection of network devices (in our case, BreadCrumbs), each of which is linked to one
or more other BreadCrumbs. Data can move between BreadCrumbs via these links, possibly passing
through several intermediate BreadCrumbs before arriving at its final destination.
The intelligence of a BCWN is in how it adapts rapidly to the creation or destruction of the links in
the mesh as devices are moved, switched O or ON, blocked by obstructions, interfered with by
other devices, or otherwise affected. This adaptation takes place automatically and immediately as
needed.
Note
Although all BreadCrumbs can be access points, most access points do not provide
mesh capability. Traditional access points simply allow wireless devices within
range to connect to a wired network; they do not extend range through other access
points.
1.2.2 BreadCrumbs Mesh by Channel and ESSID
Two BreadCrumbs establish a mesh link to each other when they share both a radio channel and an
ESSID. An ESSID is essentially a name for a wireless network. By default, BreadCrumb ME3 uses
the ESSID “breadcrumb54-v10.” Also by default, BreadCrumb ME3-09 model devices use channel
6, and BreadCrumb ME3-24 model devices use channel 11.
The following examples illustrate the use of channels and ESSIDs:
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Example 1:
Suppose you have three BreadCrumbs, called A, B, and C. Each has two radios. BreadCrumb A’s
radios are on channels 1 and 8, B’s are on 8 and 11, and C’s are on 1 and 11. All three BreadCrumbs
are using the default ESSID of "breadcrumb54-v10." Assuming that all three BreadCrumbs are
within radio range of one another, the network will be connected, as shown below:
Example 2:
Now suppose that you change the ESSID of BreadCrumb C to "lonely". The network will adjust to
this change, resulting in the following configuration:
Note that BreadCrumb C can no longer communicate with A or B, and vice versa.
1.3 Description of BreadCrumb E3
BreadCrumb ME3 is a portable, battery operated, wireless device deployable in almost any
environment. It is light in weight, offers one external antenna and a rechargeable battery, and is
designed to be completely mobile as worn by an individual.
3
Figure 1: All BreadCrumbs Use the Same ESSID.
CHANNEL 1
CHANNEL 11
CHANNEL 8
RADIO 2
BREADCRUMB B
RADIO 1
RADIO 1
BREADCRUMB C
RADIO 2RADIO 1
BREADCRUMB A
RADIO 2
Figure 2: ESSID of BreadCrumb C Changes to "lonely."
CHANNEL 8
RADIO 2
BREADCRUMB B
RADIO 1
RADIO 1
BREADCRUMB C
RADIO 2RADIO 2
BREADCRUMB A
RADIO 1
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1.3.1 Radio
BreadCrumb ME3 comprises one 802.11g radio, which depending on the ME3 model, operates
either in the 900 MHz or the 2.4 GHz frequency band. The ME3 model versus radio frequency
options are listed in Table 1 below.
Table 1: E3 odel versus Radio Frequency.
ME3 Model Radio Frequen y
ME3-24 2.4 GHz
ME3-09 900 MHz
The two possible radios support the following channels and frequencies in the United States and
Canada (see Table 2 and Table 3):
Note
Not all channels are allowed for use everywhere around the world. Check with the
corresponding wireless spectrum regulatory body to determine the subset of
channels authorized for use in your country.
Table 2: 2.4 GHz Radio Channels and Frequencies.
Channel Number Center Frequen y (MHz)
1
2412
2
2417
3
2422
4
2427
5
2432
6
2437
7
2442
8
2447
9
2452
10
2457
11
2462
The default channel for a 2.4 GHz BreadCrumb radio is 11 (2462 MHz).
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Table 3: 900 Hz Radio Channels and Frequencies.
Channel Number Center Frequen y (MHz)
5
912
6
917
The default channel for a 900 MHz BreadCrumb radio is 6 (917 MHz).
1.3.2 Enclosure
The ME3 enclosure has been designed to operate in extreme conditions with protection against
ingress of dust as well as protection against immersion in water. The enclosure dimensions are 176
mm x 95 mm x 48 mm (6.94” x 3.75” x 1.88”).
The external features of the enclosure are shown in igure 3 below.
5
Figure 3: BreadCrumb E3 Enclosure Features.
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1.3.3 18-Pin Amphenol Connector
The majority of the signals and features of BreadCrumb ME3 can be accessed through the 18-pin
Amphenol connector on the enclosure (see igure 4). The most important of these interfaces are
external power, Ethernet, and USB, which are described in more detail in the following sections.
The 18-pin Amphenol connector interfaces to the ME3 cable assembly that provides access to the
Ethernet and USB ports of the device, and to the external power supply.
1.3.3.1 Power
The external power interface to BreadCrumb ME3 resides on the 18-pin Amphenol connector (see
igure 3 and igure 4). The device accepts external power in the range of 6 VDC to 16 VDC @ 15
W. However, to charge the internal ME3 battery pack at least 9 VDC input is required.
BreadCrumb ME3 ships with a 12 V, 35 W AC/DC external power supply. This power supply in
turn connects to the 4-pin Amphenol connector on the ME3 cable assembly to provide power to the
device.
The power consumption of BreadCrumb ME3 ranges from a minimum of about 6 W at idle to a
maximum of about 10 W at full load, using the ME3 external power supply. In general, the device is
more efficient at lower voltages.
1.3.3.2 Ethernet
BreadCrumb ME3 contains two 10/100 Base-TX Ethernet ports, which can be accessed through
6
Figure 4: 18-Pin Amphenol Connector.
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the18-pin Amphenol connector on the enclosure (see igure 3 and igure 4). The ports support Auto
MDI/MDIX allowing the use of either straight-through or crossover data cables for connections.
The data interface includes electrostatic discharge, and electrical fast transient/burst immunity
compliant to the IEC 61000-4-2, and IEC 61000-4-4-E T standards, respectively.
The ME3 cable assembly plugs into the 18-pin Amphenol connector and provides a standard RJ-45
Ethernet connector for easy access to the the first ME3 Ethernet port.
Note
The standard ME3 cable assembly does not provide access to the second ME3
Ethernet port. or a custom cable assembly that provides access to both Ethernet
ports, please inquire your Rajant sales representative.
1.3.3.3 USB
The signals that interface to the BreadCrumb ME3 device's USB port are located on the 18-pin
Amphenol connector on the enclosure (see igure 3 and igure 4). The port is compliant to the
Enhanced Host Controller Interface (EHCI) and USB Transceiver 2.0 Macrocell Interface (UTMI+)
Level 2 specifications. The port supports all three standard data transfer rates of low speed
(1.5Mbps), full speed (12Mbps), and high speed (480Mbps). The power switch for the port includes
over current protection, thermal protection, in-rush current limiting, and hot-plug noise filtering.
The USB port can be used to perform BreadCrumb firmware upgrades. It can also interface to an
optional GPS receiver accessory available from Rajant.
1.3.4 Antenna Connector
BreadCrumb ME3 provides one Type N antenna connector located on the top side of the enclosure
(see igure 3).
Warning To avoid possible damage to the BreadCrumb radio, always connect or disconnect
the external antenna with the power to the BreadCrumb ME3 off.
1.3.5 Status LED
The Status LED (see igure 3) indicates the current status of a BreadCrumb. The Status LED
combines the three base colors of red, green and blue to display a broader spectrum of colors. The
meanings of the color code indicators are given in the table below:
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Table 4: Status LED Color Codes.
Color Status
Blinking Red 1
Error
Solid Blue Ready, but no peers
Solid Green At least one 24 Mbps or higher peer
Blinking Green At least one peer
Blinking Yellow
(at an accelerating rate) Progress
Blinking Yellow 1
(with short and long pauses between blinks) Warning
All Status LED colors scrolling in succession Success/Completion
Note
During a boot-up, the BreadCrumb ME3 Status LED initially starts as turned off.
Then, if the LED state is ON (see Section 1.3.6.2) it first becomes solid yellow, then
cyan, then cycles between red, blue, and green until the boot-up is complete. When
the boot-up is complete, the Status LED can display either one of the color codes
listed in Table 4 above.
1.3.6 Zeroize Keys and Restore Factory Defaults / LED Configuration
Switch
The Zeroize Keys and Restore actory Defaults / LED Configuration Switch (see igure 3) has two
modes of operation. The modes are set by the length of time the switch is asserted. The modes are:
•Zeroize Keys and Restore actory Defaults
•LED Configuration
1.3.6.1 Zeroize Keys and Restore Factory Defaults
This mode is is used to erase the security protocol keys of a BreadCrumb and to restore its software
configuration to the factory default state. To operate this switch follow these procedures:
•Ensure that the BreadCrumb is powered on, has fully booted-up and its Status LED (see
igure 3) color is green or blue (see Table 4).
•Press and hold the switch for approximately 10 seconds until the Status LED changes to the
blinking yellow progress indicator (see Table 4). This indicates that the Zeroize Keys and
Restore actory Defaults operation has been initiated and is in progress.
1 or a list of error and warning codes refer to Appendix A at the end of this document.
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•Release the switch.
•When the Zeroize Keys and Restore actory Defaults operation is complete, the Status LED
changes to the error indicator of blinking red (see Table 4 above and error code 32 in
Appendix A ). The BreadCrumb will then wait for about 30 seconds before rebooting
automatically.
ip
The process of zeroizing keys and restoring factory defaults can also be performed
remotely from within the BC|Commander management software. or details on this
alternative method, refer to the BC|Commander User Guide document.
1.3.6.2 LED Configuration
This mode is used to control the default and alternate display states of the Status LED. The LED
Configuration function is accessed by pressing the switch and releasing it after a two second hold.
The default state of the Status LED is defined as the state that the LED is in after a BreadCrumb has
been reset and has completed its boot process. The user can then toggle between the alternate and
default states of the Status LED by pressing the switch and activating the LED Configuration
function.
The default display state of the Status LED is dictated by the LED mode setting that is configured
from BC|Commander (please refer to the BC|Commander User Guide document for a more detailed
description of the LED mode setting).
Table 5 illustrates the possible default and alternate display states of the Status LED.
Table 5: Default and alternate display states of the Status LED.
Default State Alternate State
ON O
ALERTS ONLY ON
O ON
Note that state changes can occur only between options in the same rows of the table above. or
example, it is possible to toggle the state back and forth between ALERTS ONLY and ON, but not
between ALERTS ONLY and O . Transitioning from ALERTS ONLY to O would require
changing the LED mode setting in BC|Commander.
The Status LED is capable of displaying alerts, error codes, and link states. When the LED is ON,
errors, warnings, and link status are displayed. When the LED is O , errors, warnings, and link
states are not displayed. When the LED is set for ALERTS ONLY mode, only warnings and errors
are displayed.
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Warning The BreadCrumb ME3 Status LED may exhibit a short blink after a warm reset
condition that occurs due to system error or is initiated by the user (e.g., performing
a reboot command through BC|Commander, performing the Zeroize Keys and
Restore actory Defaults procedure). The LED must be physically masked (such as
adding tape to the LED lens) to guarantee that no light is emitted at any time.
1.3.7 Internal Battery
BreadCrumb ME3 contains a polymer Lithium-ion internal battery with 3600 mAh nominal
capacity, and 3.7 V nominal voltage. The battery is used only when the ME3 detects that no external
power supply is connected to the device.
The battery status can be monitored through BC|Commander. or more information on battery
status monitoring refer to the BC|Commander User Guide document.
Caution The internal battery will charge only when the external power supply voltage is 9 V
or greater.
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2 Using BC|Commander
BC|Commander is Rajant’s software package used for monitoring the status of BreadCrumbs with
version 10 firmware on a BreadCrumb Wireless Network (BCWN). BC|Commander is also used
for configuring version 10 BreadCrumbs and to graphically portray the network topology.
Note
BC|Commander includes an option called v10 Transitional Mode. This allows a
user to run a mixture of BreadCrumbs with firmware version 9 and firmware
version 10 within the same mesh network. This is very useful when BreadCrumbs
in a very large network are being upgraded from version 9 to version 10 firmware.
BC|Commander is typically run on a laptop PC, but can be run on any PC that has access to the
entire BCWN. Versions of either software package are available for Microsoft Windows® or Linux.
Note
Some portions of the BC|Commander User Guide document assume a working
knowledge of TCP/IP networking, including DHCP, NAT and DNS. While the
network lay person may be able to perform some BCWN management tasks, it is
recommended that network configuration be performed by experienced network
administrators.
Note
The BC|Commander version used must be equal to or greater than the
firmware version running on any administered BreadCrumbs in order to
administer all BreadCrumb firmware features covered in Rajant’s BC|Commander
User Guide.
Rajant periodically releases updated BC|Commander software. The updated software must be
obtained from Rajant. Refer to Rajant’s most recent BC|Commander User Guide document for
instructions on how to install the latest version of BC|Commander on your computer and how to use
BC|Commander with Rajant’s BreadCrumbs.
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3 Deploying the BreadCrumb Wireless Network
There are many factors which need to be taken into account when deploying the BreadCrumb
Wireless Network (BCWN). Section 3.1 describes the addressing scheme of the BCWN. Section
3.2 discusses channel assignments. Section 3.3 details some of the most commonly occurring
environmental factors that will have a major impact on the performance of the BCWN. inally,
section 3.4 details guidelines and methodology needed to follow when deploying the BCWN.
3.1 Addressing
When in gateway mode or when using its own embedded DHCP servers, the BreadCrumb Wireless
Network requires that wireless devices use IPv4 addresses in the Class A network 10.0.0.0/8 (that is,
any address that begins with ‘10.’). If you are not connected to another network, or if you are
bridging to one rather than routing to it, your wireless client devices may have any address
whatsoever.
Note
Any computers running the BC|Commander management application must have an
address in the same range as the BreadCrumbs they manage. Refer to the BC|
Commander User Guide document for the details of BreadCrumb IP adrress
configuration.
3.1.1 BreadCrumb Device Addresses
Each BreadCrumb radio has one IPv4 address in the Class A network 10.0.0.0/8. These addresses
are assigned during manufacturing and cannot be changed in the field. Rajant ensures during
manufacturing that these addresses are not duplicated between any two BreadCrumb devices.
Addresses assigned to BreadCrumb devices can be viewed using BC|Commander.
3.1.2 DHCP
Each BreadCrumb device includes an embedded DHCP server. You may safely enable the DHCP
servers of multiple BreadCrumb devices simultaneously, and it is in fact the most common case that
all BreadCrumb devices in a BCWN run DHCP servers. Address conflicts among DHCP clients are
prevented by using the unique BreadCrumb device addresses assigned at the factory as a base.
A BreadCrumb device determines its DHCP range as follows:
•Start with the first three bytes of the first radio’s IPv4 address.
•Add a low-byte range of 10 to 210.
3.2 Channel Assignments
By default, BreadCrumb ME3-09 model devices use channel 6, and BreadCrumb ME3-24 model
devices use channel 11 upon startup. In some cases, however, it may be necessary to manually set
the radios to specific channels. Refer to the BC|Commander User Guide document for the details of
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BreadCrumb channel configuration.
3.3 Physical Placement and other Considerations
Commonly occurring environmental factors have a significant impact on performance and behavior
of the BreadCrumb Wireless Network. LOS (Line of Sight) obstructions, distance, weather, and
device placement should all be considered when deploying a wireless network.
IEEE 802.11 wireless operation degrades gradually as distance increases between nodes or as
interference becomes prominent. This manifests as a data rate reduction between nodes.
The goal in planning and deploying a BreadCrumb Wireless Network is to maximize both coverage
and the data transfer rate between devices. These can be maximized by taking into consideration all
of the contributing factors described in this section.
3.3.1 Line-of-Sight
Unobstructed LOS (Line-of-Sight) is critical for optimal performance of the BCWN. Partial LOS
obstruction results in noticeable network performance degradation. Total LOS obstruction can result
in complete loss of network connectivity.
Elevating the device and external antenna will assist in providing better LOS. This can allow the
radio waves to propagate over some possible obstructions.
Unobstructed LOS is not necessary from every BreadCrumb device and wireless client to every
other BreadCrumb device and wireless client. However, each device must have unobstructed LOS
to the previous and subsequent device.
Client connectivity will degrade and drop if LOS to a BreadCrumb device can not be maintained.
3.3.2 Distance
Many factors determine acceptable distances between BreadCrumb devices when deploying a
BCWN:
•If many devices are placed too closely together, it is possible that interference will degrade
the performance of the system.
•Devices placed too far away or in R “shadows” may experience total loss of connection.
•R transmit power and receive sensitivity are important in determining the distances over
which the device will be effective.
•When placing a BreadCrumb device, check the connection status to the nearest available
device using either the BreadCrumb device’s status LED (described in section 1.3.5 Status
LED), or the BC|Commander management application. If the connection is poor or non-
existent, attempt to relocate the BreadCrumb device closer to another device until an
acceptable connection is obtained. If a poor connection or no connection is made at even
relatively close distances, you should refer to Chapter 5 Troubleshooting.
•When the connection quality is found to be acceptable from BC|Commander, the distance of
the BreadCrumb device from the network can be increased until an optimal balance between
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