® AirConnect® Site Survey Administrator Guide Version 1.5 http://www.3com.com/ http://www.3com.com/productreg Part No.
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CONTENTS 1 PREPARATION Introduction 5 Inspecting the Survey Area 5 Environmental Considerations 6 Direct-Sequence Considerations 6 Antenna Placement Considerations 6 Site Electrical Considerations 7 Requesting a Site Survey 7 2 CONDUCTING A SITE SURVEY Introduction 8 Site Survey Installation 8 CD-Rom Installation 8 AirConnect Wireless Network Trial 8 Starting the Site Survey Utility 9 Site Survey File Menu 10 Creating a New Site Survey 10 Selecting an Existing Site Survey 10 Defining a New Site Survey A
Navigating the Area Menu 14 Creating a New Survey Area 14 Selecting and Editing an Existing Survey Area 14 Clearing the Text File Log for an Open Survey Area 14 Editing the Note File for an Open Survey Area 15 Running ICMP or WNMP Tests 15 Setting ICMP or WNMP Test Parameters 15 Setting New Test Parameters 16 A AIRCONNECT OVERVIEW Introduction 17 AirConnect Network Topologies 17 Peer-To-Peer Network 18 Same-Site Separate Networks 18 Single AP Bridge 19 Multiple-AP Full Coverage Network 20 Theory of Operat
1 Introduction PREPARATION Installing an AirConnect wireless network begins with conducting a site survey. A site survey involves the use of the AirConnect Site Survey utility to determine the physical requirements for a site-specific AirConnect wireless network. A site survey analyzes the installation environment and provides users with recommendations for equipment and placement. The site may be a warehouse, manufacturing plant, office building, or retail space.
CHAPTER 1: PREPARATION The completion of the RF Site Survey Requirements document is a coordinated effort between the site survey team and the customer management team. The RF Site Survey Requirements document does not identify potential installation constraints within the customer site, nor does it recommend AP and antenna placement location. The RF Site Survey Requirements document represents a preliminary overview of the customer site, and is used as a baseline for refining site survey requirements.
Requesting a Site Survey Site Electrical Considerations 7 AirConnect APs draw power from wall outlets or over CAT 5 cabling using the AirConnect PowerBASE-T adapter. AP performance is subject to degradation due to inherent or random electrical problems or site-specific disturbances.
CONDUCTING A SITE SURVEY 2 Introduction The AirConnect Site Survey utility is used to establish a two-way data network using both stationary and mobile devices at various points within the proposed radio coverage area. Assess AP signal strength using various AP configurations. The AirConnect Site Survey utility runs under Windows 95/98, and NT. Site Survey Installation A site survey requires the AirConnect Site Survey utility be loaded on the wireless clients and the desktop computer used in the survey.
Starting the Site Survey Utility 9 To install a trial AirConnect wireless network, use the following procedure. 1 Mount the APs. Mount APs at the locations recommended on the floor plan drawing. Start with the most difficult coverage area first. Position the APs so that their antennas are not obstructed. 2 Power on the APs. Use the PowerBASE-T and interconnecting 8-wire CAT 5 cable if an AC wall socket is not conveniently located. 3 Observe AP LED behavior. Check the LEDs to verify normal boot operation.
CHAPTER 2: CONDUCTING A SITE SURVEY Site Survey File Menu Creating a New Site Survey Use the File menu to create a new survey area workspace, open an existing survey workspace, define a new survey area, save the survey workspace, upload/ download existing survey workspace data, import survey workspace data, and display recent survey information. Select New Site Survey in the File menu to open a Site Survey dialog box. Use the Site Survey dialog box to enter the site name, surveyor, and description.
Site Survey Edit Menu Site Survey Edit Menu 11 The Site Survey utility Edit menu contains Site Survey, Area, and Settings pull-down menus. Use these menus to edit an open AirConnect site survey, display a list of coverage areas within the survey, and use the Setup, Meter Settings, Sounds and Logging property pages to configure surveyor, system sounds, and test data logging information. Editing Site Survey Information Select Site Survey in the Edit menu to display the Site Survey dialog box.
CHAPTER 2: CONDUCTING A SITE SURVEY Editing Setup Properties Select Settings in the Edit menu to access the Setup, Meter Settings, Sounds, and Logging tabs. Use these dialog boxes to change default settings for the current site survey workspace. Setup Property Page Select the Setup tab to change the following default site survey workspace information: Edit Note on Error.
Navigating the View Menu 13 Logging Property Page Select the Logging property page to change the following default site survey workspace logging information. Enable Logging. Select Enable Logging to enable Short Logging Format or Detailed Logging Format. If unchecked, no logging takes place during the ping tests. The default is Short Logging Format. Short logging provides an overview of ping transmission test activity. Detailed logging provides a comprehensive review of ping test activity.
CHAPTER 2: CONDUCTING A SITE SURVEY Viewing Access Point Info Select Known APs in the View menu to display APs in range of the target wireless client. Use the Known APs dialog box to view the AP BSSID, number of associated wireless clients, wireless client type, and status and data rate. An icon next to each AP indicates whether the AP is mandatory or preferred and if the AP is associated. A list of APs within range of the wireless client is also shown.
Navigating the Area Menu Editing the Note File for an Open Survey Area Running ICMP or WNMP Tests 15 Select Edit Note in the Area menu to display the notes file for the active survey area. Use the Edit Note option to edit or delete the survey test notes entered for the active survey workspace. Select Run ICMP Test or Run WNMP Test in the Area menu to display the Site Survey Test dialog box. Use the Site Survey Test dialog box to specify ICMP or WNMP test parameters.
CHAPTER 2: CONDUCTING A SITE SURVEY Use the Site Survey Totals dialog box to display survey area final test results, including test start time, total number of tests, total number of runs, total test roundtrip time, average test roundtrip time, and total number of timeouts. The two checkboxes indicate if the user cancelled the test run and whether the test was run to completion.
A Introduction AIRCONNECT OVERVIEW AirConnect from 3Com is made up of a series of products that work together to deliver high-speed digital wireless networking. This technology provides connectivity between wireless clients and network nodes in a variety of indoor environments, and also provides bridging architecture between wired and wireless network segments. AirConnect is based on the IEEE 802.11HR standard, and delivers 11 Mbps data transfer rates.
APPENDIX A: AIRCONNECT OVERVIEW Peer-To-Peer Network The simplest AirConnect topology consists of one AP providing a single-cell network for wireless clients. In this scenario, as shown in the following figure, the wireless clients (laptop and desktop computers with the AirConnect NIC installed) communicate through the AP on a peer-to-peer network. The clients can be moved anywhere within the coverage area of the AP, and still communicate with each other.
AirConnect Network Topologies Single AP Bridge 19 Another possible AirConnect topology is a single AP bridging an Ethernet and wireless network. As shown in the next figure, the AP, wired to a network server or LAN through an Ethernet cable, serves as a network node and provides the link between the server and the wireless clients. The wireless clients can move freely throughout the coverage area of the AP while remaining connected to the server.
APPENDIX A: AIRCONNECT OVERVIEW Multiple-AP Full Coverage Network Theory of Operation This network topology will be used in most enterprise environments: multiple APs wired to an existing LAN to provide complete wireless network coverage. In this scenario, as shown in the next figure, wireless clients can roam seamlessly between different coverage areas and remain connected to the network.
Theory of Operation 21 The AP removes from its database destinations or interfaces not used for a specified time. The AP refreshes its database when it transmits or receives data from these destinations and interfaces. Filtering and Access Control The AP provides facilities to limit the wireless clients that associate with it and the data packets that can forward through it. Filters provide network security or improve performance by eliminating broadcast/multicast packets from the radio network.
APPENDIX A: AIRCONNECT OVERVIEW The radio interface conforms to IEEE 802.11 HR specifications. The interface operates at 11 Mbps using direct-sequence radio technology. The AP supports multiple-cell operations with fast, transparent roaming between cells. With the direct-sequence system, each cell operates independently. Each cell provides a 11 Mbps bandwidth. Adding cells to the network provides increased coverage area and total system capacity.
Theory of Operation 23 The PPP implementation in the AP uses the NCP as described in RFC 1220: PPP Extensions for Bridging to encapsulate packets at the Ethernet level. The PPP provides IP bridging control as defined by RFC 1172 and MAC-level bridging. The protocol provides support for PPP negotiations conforming to RFC 1661. Users cannot plug a non-AP node directly into the AP serial port, only AP-to-AP PPP links.
APPENDIX A: AIRCONNECT OVERVIEW Straight-through cable pinout: When using a modem connection, one AP represents the originating AP and the other represents the answering AP. When using a PPP link, do not use the serial port to access the UI. Access to the UI requires establishing a Telnet session with the AP.
Theory of Operation Wireless Client Association Process 25 APs recognize wireless clients as they associate with the AP. The AP keeps a list of the wireless clients it services.
APPENDIX A: AIRCONNECT OVERVIEW ■ The ratio of good-transmitted packets to attempted-transmitted packets falls below a threshold. ■ The wireless client detects an imbalance in the number of wireless clients associated with available APs and roams to a less loaded AP. A wireless client selects the best available AP and adjusts itself to the AP direct-sequence channel to begin association. Once associated, the AP begins forwarding any frames it receives addressed to the wireless client.
Theory of Operation 27 The AirConnect Mobile IP (roaming across routers) feature enables a wireless client on the Internet to move from one subnet to another while keeping its IP address unchanged. The scanning and associating process continues for active wireless clients. This allows the wireless clients to find new APs and discard out-of-range or deactivated APs. By testing the airwaves, the wireless clients can choose the best network connection available.
APPENDIX A: AIRCONNECT OVERVIEW A TIM is a compressed virtual bitmap identifying the AP associated wireless clients in PSP mode that have buffered directed messages. wireless clients issue a poll request when APs issue a TIM. A beacon with the broadcast-indicator bit set causes the wireless client to note DTIM Count field value. The value informs the wireless client of the beacons remaining before next DTIM.
Theory of Operation 29 Programmable SNMP Trap Support The SNMP protocol defines the method for obtaining information about networks operating characteristics and changing router and gateway parameters. The SNMP protocol consists of three elements: ■ Management stations ■ Management information ■ Management protocol (MIB) Nodes can perform as hosts, routers, bridges or other devices that can communicate status information.
APPENDIX A: AIRCONNECT OVERVIEW Using the User Interface The User Interface (UI) is a text-based maintenance tool integrated into the AP. It provides statistical displays, AP configuration options, and firmware upgrades. Access to the UI requires one of the following: Method Description Telnet Client Gain access to the AP built-in Telnet server from any AP interface including remote Ethernet connections.
