3Com 3CRWEASY96A User Manual

Wireless LAN Outdoor Bridge Solution

3CRWEASY96A

Complete Building-to-Building Outdoor Wireless LAN Kit

User Guide

http://www.3com.com/
http://support.3com.com/registration/frontpg.pl/

Published February, 2003
Document Version 1.2.0

3Com Corporation

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Parkway
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95052-8145

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If you are a United States government agency, then this documentation and the software
described herein are provided to you subject to the following:

All technical data and computer software are commercial in nature and developed solely at
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a trademark of the Wireless Ethernet Compatibility Alliance.

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This product contains Encryption and may require US and/or Local

Contents

1

Introduction

Basic Network Topologies 7

Point-to-Point 7
Point-to-Multipoint 8

Basic Operating Modes 9

Installing the Outdoor Bridge

2

Installation Requirements 10

Power Requirements 10
Administration Requirements 11

Installation Guidelines 11

Proper Grounding 11
Alignment 12
Polarization 12

Restrictions on Antenna Use 12
Safety Information 13
Mounting the Bridge to a Mast 14
Connecting the Bridge to the LAN 15

Using the Power Supply 15

Using a Power-Over-Ethernet LAN Port 15
Installing Software Utilities 16
Establishing Wireless Association 17

3

Configuring the Building-to-Building Bridge

Using the 3Com Wireless Device Manager 18

Launching a Wireless Device Configuration 18

Using the Pre-IP Configuration Wizard 20

Using the RSSI Monitor 20
Saving Configuration Changes 21
Changing System Properties 21
Setting IP Network Properties 22

Setting up Protocol and Port Filtering 23
Setting Wireless Network Properties 24
Setting Advanced Performance Properties 26
Setting up an Ad Hoc Network 28
Optimizing an Ad Hoc Installation 29
Setting up an Access Point Infrastructure Network 30
Changing Security Settings 31

No Security (Open System) 32

40-bit Shared Key (Wi-Fi) 32

128-bit Shared Key 33

128-bit Dynamic Security Link 33

Setting up the Wireless Network Login 33
Resetting the Bridge 33
Restoring a Bridge to Factory Defaults 34
Upgrading the System 34
Changing the Administration Password 35
Backing up a Configuration 35
Restoring a Configuration 36
Viewing the Client List 36

Resetting Statistics Listings 37

Clearing the Client List 37
Viewing Connection Status 37
Viewing the System Summary 37
Interoperating with Third-Party Equipment 37

4

Troubleshooting

Diagnosing Problems 38
Disconnecting the Bridge 40
Uninstalling Software and Documentation 40
Upgrading Bridge Firmware 40

Technical Support

A

Online Technical Services 41
Support from Your Network Supplier 42
Support from 3Com 42
Returning Products for Repair 43

Regulatory Compliance Information

Index

1

ASIC NETWORK TOPOLOGIES

B

I

NTRODUCTION

The 3Com® Wireless LAN Outdoor Bridge Solution is a comprehensive
building-to-building outdoor wireless LAN kit that reduces the need to evaluate,
purchase and assemble separate components. One convenient package includes
everything you need to offer an easy-to-manage building-to-building wireless
LAN. The package features a 3Com Wireless LAN Building-to-Building Bridge with
integrated antenna and power-over-Ethernet cable in a durable,
weatherproof enclosure.

This all-in-one wireless LAN solution delivers three to four times the bandwidth of
T1 links, with significantly lower operational costs. The wireless bridge lets you
connect cross-campus buildings, or portable or temporary classrooms, at
distances up to 16 kilometers (10 miles), where local regulations allow. The
building-to-building bridge interoperates seamlessly with other Wi-Fi certified
access points in large multi-vendor environments.

The 3Com bridge can be used in two types of wireless network topologies:

■

Point-to-point
Point-to-multipoint

■

OINT-TO-POINT

P

Point-to-point topology is the simplest way to use the 3Com bridge, and it offers
the highest performance level. Two 3Com outdoor bridges form a direct wireless

7

association between the wired LANs in two remote buildings. See the following
diagram of the point-to-point topology.

P

OINT-TO-MULTIPOINT

Point-to-multipoint topology allows communication among three or more
buildings. In the central building, an access point equipped with an
omnidirectional antenna provides wireless association among the wired LANs in
the other buildings where 3Com outdoor bridges are installed.

If a 3Com 11 Mbps Wireless LAN Access Point 8000 is used (with an 8dBi
omnidirectional antenna) this topology can connect wired LANs over distances up
to 10 kilometers (6 miles). If an access point from another Wi-Fi compliant
manufacturer is used, the range depends on that manufacturer’s device
limitations.

8

B

ASIC OPERATING

Two operating modes relate to the basic WLAN topologies:

■

■

M

ODES

Ad hoc mode is the basis for point-to-point topology. Operating in ad hoc
mode, two outdoor bridges can associate without an access point, allowing
the LANs to which they are connected to communicate.

Access Point (Infrastructure) mode is the basis for point-to-multipoint
topology. Operating in access point mode, multiple 3Com outdoor bridges act
as clients to an Access Point 8000 or a Wi-Fi compliant access point from
another manufacturer.

9

2

I

NSTALLING THE

This equipment must be installed in compliance with local and national building
codes, regulatory restrictions, and FCC rules. For the safety of people and
equipment, only professional network personnel should install the bridge, cables,
and antennas.

O

UTDOOR

B

RIDGE

CAUTION

Information” on page 13.

I

NSTALLATION REQUIREMENTS

The following items are required for installation:

■

■

■

■

■

■

P

OWER REQUIREMENTS

The bridge complies with the IEEE 802.3af power-over-Ethernet standard. It
receives power over outdoor rated Ethernet cable (3Com part number 3CWE487
recommended). Installation requires the use of either the 3Com power supply
provided or IEEE 802.3af compliant power supply equipment (output power rated
48 V dc @ 200 mA minimum). Such equipment must b
to UL, CSA, IEC or other applicable national or international safety requirements

: Before installing, see the important warnings and cautions in “Safety

For a point-to point configuration, two 3Com outdoor bridges.
For a point-to-multipoint configuration, one 3Com 11Mbps Wireless LAN

Access Point 8000 (or other Wi-Fi compliant access point) with an
omnidirectional antenna for one building, and one 3Com outdoor bridge for
each other building.

Mounting hardware (supplied with each bridge).
Properly grounded outdoor mast or wall mount.
Lightning arrestor properly grounded at each building in the topology.
Outdoor rated category 5 Ethernet cable (3Com part number

3CWE487 recommended).

e

safety certified according

10

for the country of use. All references to the power supply in this document refer
to equipment that meets these requirements.

Because the power supply plug is the only means of disconnecting the bridge
from power, make sure the power outlet is accessible.

See “Using the Power Supply” on page 15 and “Using a Power-Over-Ethernet
LAN Port” on page 15.

Note for use of the 3Com power supply (part number 61-0107-000) in Norway:
This product is also designed for use on an IT power system with phase-to-phase
voltage of 230 V.

A

DMINISTRATION REQUIREMENTS

To use the administration tool, which helps you select 3Com wireless LAN devices
and launch their configuration management systems, you need a computer
running one of the following operating systems and one of the
following browsers:

Operating Systems

Browsers

I

NSTALLATION GUIDELINES

The 3Com outdoor bridge is housed in a durable, waterproof enclosure and is
specifically designed for outdoor use in most climates. Optimal performance can
be maintained at outdoor temperature ranges from -20˚ C to 50˚C (-4˚F to 122˚F).
It is extremely important to avoid mounting the bridge in any area where it could
be vulnerable to extreme or hazardous conditions of any kind. Nor should the unit
be mounted flush with the roof of a building.

P

ROPER GROUNDING

To ensure the physical safety of anyone near the bridge and to prevent damage to
the unit, follow the building codes for antenna installations in your area. Make
certain that bridges and masts are appropriately grounded to prevent injury and

Windows XP

Windows 2000

Windows NT 4.0

Windows Me

Windows 98

Netscape 6.0 or later

Internet Explorer 5.0 or later

11

minimize damage from lightning strikes. A lightning arrestor, properly grounded
and installed at each building in the topology, will protect networking equipment
in the building, as well as the people working there, from lightning-induced
surges that travel on Ethernet cables.

A

LIGNMENT

Position bridges so that they are aimed at each other wherever possible. While
maintaining a direct line of sight between antennas helps to ensure a strong
signal, it is not strictly necessary, nor is it always possible. Conditions such as long
distances, mountainous regions, and architectural barriers could make a direct
line of sight nearly impossible to achieve.

In a campus setting, where buildings are short distances apart, and especially in a
point-to-point configuration, align each unit to point at the antenna with which it
will communicate. If you place two units at different heights, tilt them up or
down toward each other for optimal signal strength.

P

OLARIZATION

Polarization is a physical phenomenon of radio signal propagation. In general, any
two antennas that are to communicate with each other must be set for the same
horizontal or vertical polarization. If polarization on both antennas does not
match—a situation called

cross-polarization

—the link will either work poorly or

not at all. Follow these polarization guidelines:

Vertical polarization is preferred for point-to-multipoint configuration.

■

■

For point-to-multipoint configurations, the omnidirectional antenna
connected to the access point should be vertically aligned in relation to
the ground.

■

Unidirectional antennas that link with omnidirectional antennas should always
be oriented for vertical polarization.

ESTRICTIONS ON ANTENNA USE

R

The following restrictions apply to the use of the bridge’s 18 dBi antenna:

■ FCC regulations require that in the United States, use of channels 12 and 13 in

conjunction with an 18 dBi antenna is allowed only at very reduced power,
which the 3Com unit sets automatically.

■ The highest allowable power level is set automatically when the country

selection is made from the pulldown menu in the configuration tool.

■ To work properly with 18 dBi antennas, bridges must be separated by at least

61 Meters (200 Feet).

12

SAFETY INFORMATION

WARNING: Do not install the bridge near overhead power lines, electric light or
power circuits, or where it can come into contact with such circuits. Provide ten
feet or more clearance between the bridge and such power lines or circuits. Do
not install the bridge flush with the rooftop or wall. When installing the bridge, do
not come into contact with such circuits, which can cause serious injury or death.
Follow local and national codes for proper installation and grounding of antennas.

WARNING: To comply with FCC radio frequency (RF) exposure limits, antennas
should be located at least two meters (six feet) or more from the bodies of
all persons.

WARNING: Do not install the bridge or connect and disconnect cables during
periods of lightning activity.

WARNING: To avoid possible injury or damage to equipment, you must use either
the provided power supply or IEEE 802.3af compliant power supply equipment
that is safety certified according to UL, CSA, IEC, or other applicable national or
international safety requirements for the country of use. All references to power
supply in this document refer to equipment meeting these requirements.

WARNING: It is the responsibility of the installer to ensure that the
Power-over-Ethernet (POE) power supply is properly connected. Connection to any
other device, such as a standard Ethernet card or another POE supply, may result
in permanent damage to equipment, electric shock, or fire. Refer to the
installation instructions for proper installation.

WARNING: The 3Com power supply (part number 61-0107-000) input relies on a
16A rated building fuse or circuit protector for short circuit protection of the line
to neutral conductors.

CAUTION: A lightning arrestor will not prevent damage from direct lightning
strikes. It is extremely important to ensure that the bridge is installed at least 1
meter (3 feet) below the top of the grounded pole or mast.

CAUTION: If you supply your own Ethernet cable for connecting power, be sure
that it is outdoor rated category 5 straight-through (8-wire) cable that has not
been altered in any way (3Com part number 3CWE487 recommended). Use of
nonstandard cable could damage the bridge.

CAUTION: Minimize damage from direct lightning strikes by mounting the bridge
at least 1 Meter (3 feet) below the top of the mast.

13

MOUNTING THE BRIDGE TO A MAST

The bridge can be placed in any suitable outdoor location (see “Installation
Guidelines” on page 11). Refer to the adjustable mount instruction sheet that
comes with the bridge mounting hardware, and the illustrations below:

14

Make sure that all bridges
are properly oriented for
polarization as described
in “Polarization” on
page 12. Use the
polarization indicators on
the antenna panel to
guide orientation. VERT
POL indicates vertical
polarization and HORIZ
POL indicates horizontal
polarization.

CONNECTING THE BRIDGE TO THE LAN

You can connect to the LAN either through the 3Com power supply or through
IEEE 802.3af power-over-Ethernet compliant equipment.

USING THE POWER SUPPLY

The power supply can be located indoors at any point between the bridge and
the LAN access port where an accessible power outlet exists.

Connect the cable coming from the bridge to the port labeled To Access Point on
the power supply.

Connect another Ethernet cable from the port labeled To Hub/Switch on the
power supply to an Ethernet LAN port, as shown.

CAUTION: To avoid damaging network equipment, make sure that the cables
are connected from bridge to power supply to LAN as shown and
described above.

USING A POWER-OVER-ETHERNET LAN PORT

If your LAN equipment complies with the IEEE 802.3af power-over-Ethernet
standard, you can connect the bridge directly to a LAN port. For example, the

15