3Com 3CRWE876075 / WL-546 User manual

www.3Com.com
Part Number 10015153 Rev. AA
User Guide
3Com Wireless 8760 Dual-radio 11a/b/g
PoE Access Point
3CRWE876075 / WL-546
Published June, 2006

3Com Corporation
350 Campus Drive
Marlborough, MA
01752-3064
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3
Contents
1Introduction
Product Features 1-2
Security 1-2
Performance and Reliability 1-3
Virtual Access Point (VAP) Support 1-3
WDS Bridging and Spanning Tree Protocol (STP) Support 1-3
Manageability 1-4
Wireless Network Standards 1-4
802.11g 1-4
802.11a 1-5
Approved Channels 1-5
2Installing the Access Point
Installation Requirements 2-1
Power Requirements 2-2
Safety Information 2-2
Deciding Where to Place Equipment and
Performing A Site Survey 2-3
Before You Begin 2-4
Connecting the Standard Antennas 2-5
Connecting Power 2-6
Using the Power Supply 2-8
Using a Power-Over-Ethernet LAN Port 2-8
Checking the LEDs 2-9
Reset Button 2-9
Wall, Ceiling, or Electrical Box Mounting 2-10
Flat Surface Installation 2-12
Selecting and Connecting a Different Antenna Model 2-12
Installing Software Utilities 2-14

4
3Initial Configuration
Networks with a DHCP Server 3-1
Networks without a DHCP Server 3-1
Using the 3Com Installation CD 3-2
Launch the 3COM Wireless Infrastructure Device Manager (Widman)
utility 3-2
Launching the 3com Wireless Interface Device Manager 3-2
First Time Only 3-4
Using the Setup Wizard 3-4
4System Configuration
Advanced Setup 4-2
System Identification 4-4
TCP / IP Settings 4-5
RADIUS 4-8
Authentication 4-9
Filter Control 4-14
VLAN 4-16
SNMP 4-18
Configuring SNMP and Trap Message Parameters 4-18
Configuring SNMPv3 Users 4-21
Administration 4-22
Changing the Password 4-22
Telnet and SSH Settings 4-23
Upgrading Firmware 4-24
WDS and Spanning Tree Settings 4-27
System Log 4-33
Enabling System Logging 4-33
Configuring SNTP 4-34
Radio Interface 4-35
802.11a Interface 4-36
Configuring Radio Settings 4-36
Configuring Common Radio Settings 4-38
802.11b/g Interface 4-42
Configuring Wi-Fi Multimedia 4-44
Security 4-49
Wired Equivalent Privacy (WEP) 4-52

5
Wi-Fi Protected Access (WPA) 4-56
5Command Line Interface
Using the Command Line Interface 5-1
Accessing the CLI 5-1
Console Connection 5-1
Telnet Connection 5-2
Entering Commands 5-3
Keywords and Arguments 5-3
Minimum Abbreviation 5-3
Command Completion 5-3
Getting Help on Commands 5-3
Showing Commands 5-4
Partial Keyword Lookup 5-4
Negating the Effect of Commands 5-5
Using Command History 5-5
Understanding Command Modes 5-5
Exec Commands 5-5
Configuration Commands 5-6
Command Line Processing 5-6
Command Groups 5-7
6Troubleshooting
Index

6

7
TERMINOLOGY
Access Point—An internetworking device that seamlessly connects
wired and wireless networks.
Ad Hoc—An ad hoc wireless LAN is a group of computers, each with
wireless adapters, connected as an independent wireless LAN.
Backbone—The core infrastructure of a network. The portion of the
network that transports information from one central location to another
central location where it is unloaded onto a local system.
Base Station—In mobile telecommunications, a base station is the
central radio transmitter/receiver that maintains communications with the
mobile radiotelephone sets within its range. In cellular and personal
communications applications, each cell or micro-cell has its own base
station; each base station in turn is interconnected with other cells’ bases.
BSS—Basic Service Set. It is an access point and all the LAN PCs that are
associated with it.
CSMA/CA—Carrier Sense Multiple Access with Collision Avoidance.
EAP—Extensible Authentication Protocol, which provides a generalized
framework for several different authentication methods.
ESS—Extended Service Set. More than one BSS is configured to become
an ESS. LAN mobile users can roam between different BSSs in an ESS
(ESS-ID, SSID).
Ethernet—A popular local area data communications network, which
accepts transmission from computers and terminals.
Infrastructure—An integrated wireless and wired LAN is called an
infrastructure configuration.
RADIUS—Remote Access Dial-In User Server is an authentication method
used in conjunction with EAP for 802.1x authentication and session
based keys.
Roaming—A wireless LAN mobile user moves around an ESS and
maintains a continuous connection to the infrastructure network.
RTS Threshold—Transmitters contending for the medium may not be
aware of each other (they are “hidden nodes”). The RTS/CTS mechanism
can solve this problem. If the packet size is smaller than the preset RTS
Threshold size, the RTS/CTS mechanism will not be enabled.

8
VAP—Virtual Access Point. An access point radio capable of operating as
four separate access points.
VLAN—Virtual Local Area Network. A LAN consisting of groups of hosts
that are on physically different segments but that communicate as
though they were on the same segment.
WEP—Wired Equivalent Privacy is based on the use of security keys and
the popular RC4 encryption algorithm. Wireless devices without a valid
WEP key will be excluded from network traffic.
WDS—Wireless Distribution System.
WPA—Wi-Fi Protected Access.

1-1
1INTRODUCTION
The 3Com® Wireless 8760 Dual-radio 11a/b/g PoE Access Point offers a
dual-mode architecture that supports 802.11g, 802.11a, and 802.11b wireless
users on a single device. This means you can mix and match radio bands to meet
different coverage and bandwidth needs within the same area.
With their flexibility and unfettered access, wireless LANs are changing the way
people work. Now with 3Com’s enterprise-class wireless access point, you can
build a cost-effective, reliable, secure wireless network that provides users with
seamless connectivity to the Internet, company intranet, and the wired corporate
network from anywhere they happen to be—conference room, cafeteria or
office.
3Com’s dual-mode design supports 802.11g, 802.11a, and 802.11b wireless
standards on a single access point. This capability increases configuration and
coverage flexibility and protects your network investment for both existing and
emerging wireless standards.
Industry-leading security features and comprehensive management and
performance features combine to make these enterprise class wireless access
points an ideal choice for organizations ready to serve their increasingly mobile
workforce.

1-2
CHAPTER 1: INTRODUCTION
PRODUCT FEATURES
Access Point 8760—Creates an enterprise-class wireless LAN supporting up to
256 simultaneous users. The access point supports two radios and external
antennas including WDS bridging ability on both radios.
SECURITY
3Com offers one of the most robust suite of standards-based security on the
market today.
To protect sensitive data broadcast over the wireless LAN, 3Com supports WPA
and WPA2 security standards. 3Com strengthens this basic security mechanism
with additional security features, including:
MAC address access control lists
IEEE 802.1x per-port user authentication with RADIUS server support
IEEE 802.1x supplicant support
SSH v2
HTTP/HTTPS
SNMP v3
Legacy WEP 40/64 bit, 128 bit and 152 bit
Wireless Protected Access (WPA) and WPA2
Extensible Authentication Protocol (EAP) support: EAP-MD5, EAP-TLS,
EAP-TTLS, and PEAP

1-3
Product Features
PERFORMANCE AND RELIABILITY
3Com wireless access point performance features ensure reliable and seamless
connections for users wherever they roam:
Automatic channel selection automatically finds the least loaded channel for
interference-free communication.
Auto network connect and dynamic rate shifting keep users connected
through a wide variety of conditions by changing to the optimum connection
speed as they move through the network.
Virtual Access Point (VAP) support provides flexibility by allowing a single
access point radio to operate as up to four separate access points.
Wireless Distribution System (WDS) Bridging support allows you to create
large wireless networks in areas where pulling wires is restricted or
cost-prohibitive by linking several wireless access points together with WDS
links.
Virtual Access Point (VAP) Support
Virtual Access Point (VAP) support allows an access point radio to operate as four
separate access points, providing multiple wireless services to clients in a network.
Each VAP can be configured to provide access to different network resources and
can support different levels of security.
For example, in a university network, an access point (AP) could be used to offer
two services: The first service provides access to protected data for authenticated
university staff members, while the second service provides open access to the
Internet for unauthenticated users, such as students or visitors.
Up to four VAPs per radio are available, and each VAP can be configured with its
own security settings.
For information on setting up and configuring VAPs, see “Wired Equivalent
Privacy (WEP)” on page 4-52.
WDS Bridging and Spanning Tree Protocol (STP) Support
A Distribution System (DS) is a network (typically a wired network) that
interconnects separate access points into a single LAN. With WDS, the
interconnection no longer needs to be physically wired. WDS uses the wireless
medium to interconnect separate access points, thereby eliminating the cost and
inconvenience that may hinder wire installations.
A WDS link can be used in a simple point-to-point link, a complex
point-to-multipoint link, or a multilayer topology.

1-4
CHAPTER 1: INTRODUCTION
MANAGEABILITY
3Com offers a wide range of standards-based management support, from SNMP
to 3Com Network Supervisor and HP OpenView for seamless integration with
your wired network.
Wireless Infrastructure Device Manager lets you configure parameters, run
diagnostics, backup and restore configurations, and monitor performance from
anywhere on the network using an embedded web server browser.
With Power over Ethernet (PoE) support, the same Category 5 cable that
connects your access point to the data network also provides its power. A single
cable installation dramatically improves your choice of mounting configurations
because you no longer need to consider AC power outlet locations. PoE support
makes it easier than ever to overcome installation problems with difficult-to-wire
or hard-to-reach locations.
WIRELESS NETWORK STANDARDS
Understanding the characteristics of the 802.11g and 802.11a standards can help
you make the best choice for your wireless implementation plans.
802.11G
802.11g operates in the 2.4 GHz band at up to 54Mbps, and supports the widest
coverage—up to 100 meters (328 feet). However, is subject to a greater risk of
radio interference because it operates in the more popular 2.4 GHz band.
For those organizations demanding even higher speeds, a “turbo mode” feature
can boost throughput rates up to 108 Mbps. Consider 802.11g when you need
wider coverage and vendor compatibility and you are:
Maintaining support for existing 802.11b users and the existing wireless
investment while providing for expansion into 802.11g.
Implementing a complete wireless LAN solution, including bridges, gateways,
access points and clients; Wi-Fi certification guarantees compatibility
among vendors
Providing access to hot spots in public spaces such as coffee shops or
university cafeterias

1-5
Wireless Network Standards
802.11A
802.11a operates at the 5 GHz band and supports data rates at up to 54 Mbps.
For those organizations demanding even higher speeds, a “turbo mode” feature
can boost throughput rates up to 108 Mbps. And because there are fewer
devices in the 5 GHz band, there’s less potential for RF interference. However,
because it is at an entirely different radio spectrum, it is not compatible with
802.11g.
The higher spectrum provides about 50 meters (164 feet) of coverage—about
half what 802.11g offers.
Consider 802.11a when you need high throughput in a confined space and you are:
Running high-bandwidth applications like voice, video, or multimedia over a
wireless network that can benefit from a fivefold increase in data throughput
Transferring large files like computer aided design files, preprint publishing
documents or graphics files, such as MRI scans for medical applications, that
demand additional bandwidth
Supporting a dense user base confined to a small coverage area. Because
802.11a has a greater number of non-overlapping channels, you can pack
more access points in a tighter space.
APPROVED CHANNELS
Use of this product is only authorized for the channels approved by each country.
For proper installation, select your country from the country selection list.
To conform to FCC and other country restrictions your product may be limited in
the channels that are available. If other channels are permitted in your country
please visit the 3Com website for the latest software version.

1-6
CHAPTER 1: INTRODUCTION

2-1
2INSTALLING THE ACCESS POINT
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, this product must be installed by a professional technician/installer.
INSTALLATION REQUIREMENTS
The following items are required for installation:
Access Point 8760.
Two standard detachable antennas.
3Com installation CD.
Wall-mount installation hardware (supplied): mounting plate,
mounting screws, and plastic anchors for drywall mounting.
If you do not have IEEE 802.3af power-over-Ethernet LAN equipment, use the
3Com Integrated Power-over-Ethernet power supply that comes with
the access point.
If your LAN equipment complies with the IEEE 802.3af power-over-Ethernet
standard, you can connect directly to the equipment, and the 3Com power
supply is not needed.
Standard category 5 straight (8-wire) Ethernet cable.
The cable must be long enough to reach the power supply or the
power-over-Ethernet LAN port.
If you use the 3Com power supply, you need an additional Ethernet cable to
connect the access point to the LAN.
CAUTION: Before installing, see the important warnings and cautions in “Safety
Information” on page 2-2.
!

2-2
CHAPTER 2: INSTALLING THE ACCESS POINT
To access and use the Web configuration management system, you need a
computer that is running Internet Explorer 5.0 or newer and one of the
following operating systems: Windows 2000, or Windows XP. It is
recommended that this computer become the dedicated workstation for
managing and configuring the access point and the wireless network.
POWER REQUIREMENTS
The access point complies with the IEEE 802.3af power-over-Ethernet standard. It
receives power over standard category 5 straight (8-wire) Ethernet cable.
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 @
400 mA maximum). Such equipment must be safety certified according to UL,
CSA, IEC or other applicable national or international safety requirements 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 access
point from power, make sure the power outlet is accessible.
See “Using the Power Supply” on page 2-8 and “Using a Power-Over-Ethernet
LAN Port” on page 2-8.
SAFETY INFORMATION
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 access point,
cables, and antennas.
CAUTION: If you supply your own Ethernet cable for connecting power, be sure
that it is category 5 straight-through (8-wire) cable that has not been altered in
any way. Use of nonstandard cable could damage the access point.
CAUTION: To comply with FCC radio frequency (RF) exposure limits, a minimum
body-to-antenna distance of 20 centimeter (8 inches) must be maintained when
the access point is operational.
CAUTION: 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.
!
!
!

2-3
Deciding Where to Place Equipment and Performing A Site Survey
DECIDING WHERE TO PLACE EQUIPMENT AND
PERFORMING A SITE SURVEY
The access point is ideally designed for vertical installation on a wall surface, but
can also be flat-surface mounted in an elevated location where it will not
be disturbed. Ceiling installation is not recommended.
Whether you choose to mount the access point on a wall or place it on a flat
surface, make sure to select a clean, dry location that is elevated enough to
provide good reception and network coverage. Do not mount the access point on
any type of metal surface. Do not install the access point in wet or dusty areas.
The site should not be close to transformers, heavy-duty motors, fluorescent
lights, microwave ovens, refrigerators or any other electrical equipment that can
interfere with radio signals.
If you are connecting the access point to a wired network, the location must
provide an Ethernet connection. You will need to run an Ethernet cable from the
power supply to the access point.
An access point provides coverage at distances of up to 100 Meters (300 Feet).
Signal loss can occur if metal, concrete, brick, walls, floors or other architectural
barriers block transmission. If your location includes these kinds of obstructions,
you may need to add additional access points to improve coverage
CAUTION: The 3Com power supply input relies on a 16A rated building fuse or
circuit protector for short circuit protection of the line to neutral conductors.
CAUTION: 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.
!
!

2-4
CHAPTER 2: INSTALLING THE ACCESS POINT
Configuring a wireless LAN can be as easy as placing a 3Com Wireless Access
Point in a central area and making the necessary connections to the AP and the
clients. However, installing multiple Access Points may require more planning.
If you plan to use an optional antenna instead of the standard detachable
antennas that are supplied, review “Selecting and Connecting a Different
Antenna Model” on page 2-12 before selecting the final location and be sure to
allow for routing the antenna cable as required.
For optimal performance, ensure the access point operates in temperature ranges
between 0° C to 50° C (14° F to 122° F).
BEFORE YOU BEGIN
Record the access point MAC address in a safe place before the access point is
installed in a hard-to-reach location. The MAC address is printed on the back of
the access point housing.
The following illustration shows the front and rear views of the access point,
including the LEDs and connecting ports.
CAUTION: Regulatory restrictions dictate that when this device is operational,
the minimal body-to-antenna distance is 20 cm (8 inches).
!

2-5
Connecting the Standard Antennas
Figure 1 Front and Rear Panel Description
CONNECTING THE STANDARD ANTENNAS
The Access Point 8760 is supplied with standard detachable antennas. These
should be attached before the access point is installed. If using an alternate
antenna, see “Selecting and Connecting a Different Antenna Model” on
page 2-12.
1Carefully unpack the standard detachable antennas.
2Screw an antenna into each of the sockets in the access point housing.
3Hand-tighten the antennas at the very base of the RSMA connectors.
4Position the antennas so they turn out and away from the access point at a
45-degree angle. After network startup, you may need to adjust the antennas
to fine-tune coverage in your area.
LEDs
Kensington Lock Slot
POE Port
Console Port
CAUTION: Do not handle the antenna tips, especially after they are connected
to the access point, as this could lead to electrostatic discharge (ESD), which
could damage the equipment.
!

2-6
CHAPTER 2: INSTALLING THE ACCESS POINT
Figure 2 Antenna Adjustment
Depending on the coverage required for your site, you may want to replace
the standard detachable antennas with one of the external antennas available
for use with the access point. See “Selecting and Connecting a Different
Antenna Model” on page 2-12.
CONNECTING POWER
It is advisable to connect the power and check the Ethernet cables and LEDs
before installing the unit in a hard-to-reach location.
The access point complies with the IEEE 802.3af power-over-Ethernet standard. It
receives power over a standard category 5 straight (8-wire) Ethernet cable.
There are two ways to supply power to the access point:
Use the 3Com Integrated Power-over-Ethernet power supply. In this case, you
need to supply a second Ethernet cable to connect to the wired LAN.
Connect the access point directly to your own power-over-Ethernet hub or
switch, which must also comply with the IEEE 802.3af standard.