IEEE 802.11b Wireless Access Point Pro/Advanced User’s Guide Version: 2.
Federal Communication Commission Interference Statement This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiated radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
R&TTE Compliance Statement This equipment complies with all the requirements of DIRECTIVE 1999/5/CE OF THE EUROPEAN PARLIAMENT AND THE COUNCIL OF 9 March 1999 on radio equipment and telecommunication terminal equipment and the mutual recognition of their conformity (R&TTE). The R&TTE Directive repeals and replaces in the directive 98/13/EEC (Telecommunications Terminal Equipment and Satellite Earth Station Equipment) as of April 8,2000.
Table of Contents 1. Introduction ......................................................................................................................... 1 1.1. Overview................................................................................................................... 1 1.2. Features.................................................................................................................... 1 1.3. Feature Comparison ...................................................................
3.5.1.3. Association Control ............................................................................ 29 3.5.1.4. AP Load Balancing............................................................................. 29 3.5.1.5. Wireless Distribution System.............................................................. 29 3.5.2. Security......................................................................................................... 33 3.5.2.1. Basic.......................................................
1. Introduction 1.1. Overview The wireless access point (AP) enables IEEE 802.11b client computers to access the resources on the Ethernet network. There are 2 model variations, Pro, and Advanced, which are classified in terms of features. With the sleek Web-based user interface and Windows-based user interface (Wireless Network Manager), a network administrator can easily and clearly manage the AP. In Chapter 2, we describe the steps to install and configure a newly acquired AP.
Repeater. When the AP is in AP/Bridge mode, it can communicate with other APs or wireless bridges via WDS (Wireless Distribution System). Therefore, an AP can wirelessly forward packets from wireless clients to another AP, and then the later AP forwards the packets to the Ethernet network. Antenna alignment assistance. The AP provides a WDS link quality indicator via Wireless Network Manager to facilitate alignment of directional antennas when deploying pairs of wireless bridges. Link health monitoring.
Xmodem-based. Upgrading firmware over RS232. TFTP-based. Upgrading firmware by TFTP (Trivial File Transfer Protocol). HTTP-based. Upgrading firmware by HTTP (HeperText Transfer Protocol). Configuration backup. The configuration settings of the AP can be backed up to a file via TFTP or HTTP for later restoring. Configuration reset. Resetting the configuration settings to factory-default values.
1.4. LED Definitions There are several LED indicators on the housing of the AP. They are defined as follows: ALV: Alive. Blinks when the AP is working normally. RF: IEEE 802.
2. First-Time Installation and Configuration 2.1. Selecting a Power Supply Method Optionally, the AP can be powered by the supplied power adapter or PoE (Power over Ethernet). The AP automatically selects the suitable one depending on your decision. To power the AP by the supplied power adapter: 1. Plug the power adapter to an AC socket. 2. Plug the connector of the power adapter to the power jack of the AP.
Fig. 1. Mounting the AP on a wall. 2.3. Preparing for Configuration For you to configure an AP, a managing computer with a Web browser is needed. For first-time configuration of an AP, an Ethernet network interface card (NIC) should have been installed in the managing computer. For maintenance-configuration of a deployed AP, either a wireless computer or a wired computer can be employed as the managing computer.
Cross-over Ethernet cable Normal Ethernet cable Managing Computer Normal Ethernet cable Ethernet Hub/Switch Managed AP Fig. 2. Connecting a managing computer and an AP via Ethernet. You can use either a cross-over Ethernet cable (included in the package) or a switch/hub with 2 normal Ethernet cables. NOTE: One connector of the Ethernet cable must be plugged into the LAN/CONFIG Ethernet jack of the AP for configuration. 2.3.2.
right to access the Web-based Network Manager. For first-time configuration, use the default user name “root” and default password “root”, respectively. Fig. 3. Entering the user name and password. NOTE: It is strongly recommended that the password be changed to other value for security reasons. On the start page, click the General, Password link to change the value of the password (see Section 3.3.1 for more information).
2.4.2. Step 1: Selecting an Operational Mode Fig. 5. Operational modes settings. Go to the General, Operational Mode section, select an operational mode and click Save at the bottom of this page, and then you are brought back to the start page. The AP supports 2 operational modes: AP/Bridge. This mode provides both Access Point and Static LAN-to-LAN Bridging functionality. The static LAN-to-LAN bridging function is supported through Wireless Distribution System (WDS). AP Client.
Table 1. Operational modes vs. wireless link types. AP/Bridge AP Client AP/Bridge WDS STA-AP AP Client STA-AP To establish a static bridge link based on WDS, the AP/bridges at both end of the WDS link must be manually configured with each other’s MAC addresses (see Section 3.5.1.5 for more information). To establish a dynamic bridge link between an AP and an AP Client, both devices have to be configured with the same SSID and WEP settings.
2.4.4. Step 3: Configuring IEEE 802.11 Settings Fig. 7. IEEE 802.11b communication settings. Go to the IEEE 802.11, Communication section to configure IEEE 802.11b-related communication settings, including Regulatory domain, Channel number, and Network name (SSID). The number of available RF channels depends on local regulations; therefore you have to choose an appropriate regulatory domain to comply with local regulations.
2.5. Deploying the AP After the settings have been configured, deploy the AP to the field application environment. Connect the AP to an Ethernet LAN through an Ethernet switch/hub. If you are configuring a pair of the APs for a dynamic or static bridging application and external high-gain directional antennas are used, it’s difficult to adjust alignments of the antennas when the pair of devices is distance away. To adjust the alignments of a pair of bridges’ directional antennas: 1.
Fig. 10. Antenna alignment assistance. Instead of using PING.exe, you can run Wireless Network Manager on Computer 1, and go to the Antenna Alignment tab. Click Start to begin monitoring the WDS link quality. Adjust the alignment of the antenna of Bridge 1 until the Link quality indicator shows a relatively maximal value. Finally, click Stop to stop monitoring WDS link quality.
computer could be set to “any”. NOTE: Both the wireless client computer and the AP must have the same WEP settings for them to communicate with each other. NOTE: For better wireless security, IEEE 802.1x capability of the AP must be enabled so that only authenticated wireless users can access the wireless network. Refer to the IEEE 802.1x-related white papers on the companion CD-ROM for more information about deploying secure WLANs with IEEE 802.1x support. 2.6.2.
default gateway of the wireless client computer. Then press Enter. If the gateway responds, go to the next step; else, see Appendix B-2, “TCP/IP Settings Problems” for troubleshooting. 4. Type “ping 1st_dns_server”, where 1st_dns_server is a placeholder for the IP address of the primary DNS server of the wireless client computer. Then press Enter. If this DNS server responds, go to the next step; else, see Appendix B-2, “TCP/IP Settings Problems” for troubleshooting. 5.
3. Using Web-Based Network Manager In this chapter, we’ll explain each Web management page of the Web-based Network Manager. 3.1. Overview Fig. 12. The Start page. 3.1.1. Menu Structure The left side of the start page contains a menu for you to carry out commands. Here is a brief description of the hyperlinks on the menu: Home. For going back to the start page. Status. Status information. Wireless Clients. The status of the wireless clients currently associated with the AP. DHCP Mappings.
General. Global operations. Password. For gaining rights to change the settings of the AP. Firmware Tools. For upgrading the firmware of the AP, backing up and restoring configuration, and configuration reset settings of the AP. TCP/IP. TCP/IP-related settings. Addressing. IP address settings for the AP to work with TCP/IP. DHCP Server. Settings for the DHCP (Dynamic Host Configuration Protocol) server on the AP. IEEE 802.11. IEEE 802.11b-related settings. Communication. Basic settings for the IEEE 802.
Fig. 14. Settings have been changed. 3.1.3. Home and Refresh Commands Fig. 15. Home and Refresh. At the bottom of each status page that shows read-only information, there are two buttons—Home and Refresh. Clicking Home brings you back to the start page. Clicking Refresh updates the shown status information. 3.2. Viewing Status 3.2.1. Associated Wireless Clients Fig. 16. Status of associated wireless clients.
3.2.2. Current DHCP Mappings Fig. 17. Current DHCP mappings. On this page, all the current static or dynamic DHCP mappings are shown. A DHCP mapping is a correspondence relationship between an IP address assigned by the DHCP server and a computer or device that obtains the IP address. A computer or device that acts as a DHCP client is identified by its MAC address. A static mapping indicates that the DHCP client always obtains the specified IP address from the DHCP server.
tional antennas for bridging applications. Refer to Section 2.5 for more information about antenna alignment. NOTE: The values are updated every 20 seconds. 3.3. General Operations 3.3.1. Specifying Operational Mode Fig. 20. Operational modes settings. The AP supports 2 operational modes: AP/Bridge. This mode provides both Access Point and Static LAN-to-LAN Bridging functionality. The static LAN-to-LAN bridging function is supported through Wireless Distribution System (WDS). AP Client.
To establish a static bridge link based on WDS, the AP/bridges at both end of the WDS link must be manually configured with each other’s MAC addresses (see Section 3.5.1.5 for more information). To establish a dynamic bridge link between an AP and an AP Client, both devices have to be configured with the same SSID and WEP settings. The AP Client automatically scans for any AP that is using the matched SSID and establishes a bridge link with the scanned AP.
3.3.3.1. Upgrading Firmware by HTTP Fig. 23. Firmware upgrade by HTTP. To upgrade firmware of the AP by HTTP: 1. Click Browse and then select a correct firmware .bin file. The firmware file path will be shown in the Firmware file name text box. 2. Click Upgrade to begin the upgrade process. 3.3.3.2. Backing up and Restoring Configuration Settings by HTTP Fig. 24. Firmware backup by HTTP. To back up configuration of the AP by HTTP: 1. Click Back Up. 2.
3.3.3.3. Upgrading Firmware by TFTP Fig. 26. TFTP server settings. When use TFTP as the firmware management protocol, you can configure settings for the AP’s TFTP client to communicate with a TFTP server. If the TFTP client does not get a response from the TFTP server within a period specified by the Timeout setting, it will resend the previous request. The Max number of retries setting specifies the maximal number of resend before the TFTP client stops communicating with the TFTP server.
Fig. 28. TFTP Server. NOTE: After the dialog box of the TFTP server program appears, be sure to specify the working folder within which the downloaded firmware files reside. NOTE: Make sure the Accept read requests check box of TFTP Server is selected. NOTE: The LAN IP address of the AP and the IP address of the TFTP server must be in the same IP subnet for TFTP to work.
1. Get a computer that will be used as a TFTP server and as a managing computer to trigger the backup process. 2. Connect the computer and one of the LAN Ethernet switch port with a normal Ethernet cable. 3. Configure the IP address of the computer so that the computer and the AP are in the same IP subnet. 4. On the computer, run the TFTP Server utility. Select the Accept write requests check box, and specify the folder to which the configuration settings of the AP will be saved. 5.
and Max no. of retries settings of TFTP Server for remote TFTP configuration backup/restore to succeed. 3.3.3.5. Resetting Configuration to Factory Defaults Fig. 30. Configuration reset. Clicking the Reset button resets the device configuration to factory defaults. WARNING: Think twice before clicking the Reset button. You’ll lose all your current configuration settings. 3.4. Configuring TCP/IP Related Settings 3.4.1. Addressing Fig. 31. TCP/IP settings.
3.4.2. DHCP Server 3.4.2.1. Basic Fig. 32. Basic DHCP server settings. The AP can automatically assign IP addresses to client computers by DHCP. In this section of the management page, you can specify the Default gateway, Subnet mask, Primary DNS server, and Secondary DNS server settings that will be sent to a client at its request. Additionally, you can specify the first IP address that will be assigned to the clients and the number of allocateable IP addresses.
To always assign a static IP address to a specific DHCP client: 1. Specify the MAC address of the DHCP client and the IP address to be assigned to it. Then, give a description for this mapping. 2. Select the corresponding Enabled check box. 3.5. Configuring IEEE 802.11b-Related Settings 3.5.1. Communication 3.5.1.1. Basic Basic IEEE 802.11b-related communication settings include AP functionality, Regulatory domain, Channel number, Network name (SSID), Data rate, and Transmit power. Fig. 34.
3.5.1.3. Association Control Fig. 36. Association control settings. If the number of currently associated wireless clients exceeds the value specified in the Max number of clients setting, no more wireless client can associate with the AP. If traffic load of the AP exceeds the load specified in the Block clients if traffic load exceeds setting, no more wireless client can associate with the AP. 3.5.1.4. AP Load Balancing Fig. 37. AP load balancing settings.
puters. In this way, AP 2 plays a role of “AP repeater”. WDS Link LAN Segment 1 Bridge 1 LAN Segment 2 Bridge 2 Fig. 39. LAN-to-LAN bridging. By WDS, two or more LAN segments can be connected wirelessly. As illustrated in Fig. 39, a pair of wireless LAN-to-LAN bridges is used to connect two LAN segments. Since the AP is WDS-enabled, it can be used as a wireless bridge. NOTE: An AP can have up to 6 WDS links to other APs or wireless bridges. Fig. 40. Wireless Distribution System settings.
Fig. 41. Sample wireless bridge network topology. WARNING: Don’t let your network topology consisting of wireless bridges, Ethernet switches, Ethernet links, and WDS links contain loops. If any loops exist, packets will circle around the loops and network performance will be seriously degraded. Fig. 42. Network topology containing a loop. TIP: You can check whether the WDS links of the AP are functioning by using Wireless Network Manager.
Fig. 43. Link health monitoring. Run Wireless Network Manager on a computer and locate the AP you want to manage. Go to the WDS tab, and then click Test. The test results (OK or Broken) will be shown in the Link Status column of the WDS links table. If external high-gain directional antennas are used, it’s difficult to align the antennas when the distance between the bridges is long. To adjust the alignments of a pair of bridges’ directional antennas: 7. Connect each bridge to a computer via Ethernet. 8.
Adjust antenna alignment WDS Link Bridge 2 Bridge 1 PING (ICMP Echo Request) ICMP Echo Reply Computer 1 Computer 2 Fig. 44. Adjusting alignments of external directional antennas. TIP: You can make use of the Antenna Alignment Assistance feature to help you align the directional antennas. Fig. 45. Antenna alignment assistance. Instead of using PING.exe, you can run Wireless Network Manager on Computer 1, and go to the Antenna Alignment tab. Click Start to begin monitoring the WDS link quality.
3.5.2.1. Basic Fig. 46. Basic IEEE 802.11b security settings. For security reasons, it’s highly recommended that the security mode be set to options other than Open System. When the security mode is set to Open System, no authentication and data encryption will be performed. Additionally, you can disable the SSID broadcasts functionality so that a wireless client computer with an “any” SSID cannot associate with the AP.
STA 1 STA 3 STA 2 AP 1 AP 2 WCI: All APs in This Subnet WCI: All APs in This Subnet Switch Wireless Link Ethernet Link Fig. 48. Behavior of the “All APs on This Subnet” wireless client isolation option. As illustrated in Fig. 47 when AP 1 and AP 2 are using the “This AP Only” option, wireless traffic between STA 1 and STA 2 is blocked by AP 1, while wireless traffic between STA 2 and STA 3, which are associated with different APs, is still allowed.
In the above security modes, a back-end RADIUS (Remote Authentication Dial-In User Service) server is needed if IEEE 802.1x functionality is enabled. See Section 3.5.3 for more information about IEEE 802.1x and RADIUS. According to the IEEE 802.11 standard, WEP can be used for authentication and data encryption. Normally, Shared Key authentication is used if WEP data encryption is enabled. In rare cases, Open System authentication may be used when WEP data encryption is enabled.
3. Specify the MAC address of a wireless client to be denied access, and then click Add. 4. Repeat Steps 3 for other wireless clients. To delete an entry in the access control table: Click Delete next to the entry. NOTE: The size of the access control table is 64. Fig. 50. MAC ACL download settings.
IEEE 802.1x, a user has to issue his or her user name and password or digital certificate to the backend RADIUS server by EAPOL (Extensible Authentication Protocol Over LAN). The RADIUS server can record accounting information such as when a user logs on to the wireless LAN and logs off from the wireless LAN for monitoring or billing purposes. The IEEE 802.1x functionality of the access point is controlled by the security mode (see Section 3.5.2.1).
Fig. 53. IEEE 802.1x/RADIUS settings. TIP: Refer to the IEEE 802.1x-related white papers on the companion CD-ROM for more information about deploying secure WLANs with IEEE 802.1x support. 3.6. Configuring Advanced Settings 3.6.1. Packet Filters The AP provides layer 2 (Ethernet Type Filters), layer 3 (IP Protocol Filters), and layer 4 (TCP/UDP Port Filters) filtering capabilities. The configuration processes for the filters are similar.
3.6.1.2. IP Protocol Filters Fig. 55. IP protocol filters settings. The protocol, source address, and destination address fields of a packet incoming from the WLAN or Ethernet interface is inspected for filtering. In a rule, specify the hex-decimal protocol number, source IP address range (Source IP Address AND Source Subnet Mask), and destination IP address range (Destination IP Address AND Destination Subnet Mask).
3.6.2. Management 3.6.2.1. UPnP Fig. 57. UPnP settings. UPnP (Universal Plug and Play) enables a Windows XP user to automatically discover peripheral devices by HTTP. When the UPnP functionality is enabled, you can see the AP in My Network Places of Windows XP. The AP can be given a friend name that will be shown in My Network Places. Double-clicking the icon in My Network Places that stands for the AP will launch the default Web browser for you to configure the AP. 3.6.2.2. System Log Fig. 58.
3.6.2.3. SNMP Fig. 59. SNMP settings. The SNMP (Simple Network Management Protocol) functionality can be disabled, and you can specify the name (used as a password) of the read-only and read-write community. In addition, up to 5 SNMP trap targets can be set in the SNMP Trap Table. To specify a trap target: 1. Type the IP address of the target host. 2. Type the Community for the host. 3. Select the corresponding check box next to the IP address text box.
Appendix A: Default Settings TIP: Press the Default (SF-Reset, or Soft-Reset) switch on the housing of a powered-on AP to reset the configuration settings to factory-default values. Setting Name Global User Name Password IEEE 802.11b Regulatory Domain Channel Number SSID SSID Broadcasts Transmission Rate Transmit Power MAC Address Default Value root root FCC (U.S.) 11 wireless Enabled Auto High See the label on the accompanying PCMCIA card or the label on the housing of the AP.
Appendix B: Troubleshooting Check the following first: Make sure that the power of the AP is on and the Ethernet cables are connected firmly to the RJ-45 jacks of the AP. Make sure that the LED ALV of the AP is blinking to indicate the AP is working. Make sure the types of the Ethernet cables are correct. Recall that there are two types—normal and crossover. B-1: Wireless Settings Problems The wireless client computer cannot associate with an AP.
B-2: TCP/IP Settings Problems Correspondent Host IEEE 802.11b Internet Ethernet LAN Stage A Client Computer State B AP Stage D Default Gateway of Client Computer DNS Server of Client Computer Fig. 60. Communication stages for a client to reach its correspondent host. For a wireless client computer to communicate with a correspondent host on the Internet by the host’s domain name (e.g. http://www.wi-fi.com), it first sends a DNS request to a DNS server on the Internet.
Make sure the Ethernet link is OK. Make sure the wireless settings of the wireless client computer and of the AP match. Are the IP address of the client computer and the IP address of the AP in the same IP subnet? Use WinIPCfg.exe or IPConfig.exe to see the current IP address of the client computer. Make sure the IP address of the client computer and the IP address of the AP are in the same IP subnet.
Fig. 61. Wireless Router/AP Browser. The AP stops working and does not respond to Web management requests. The firmware of the AP may be stuck in an incorrect state. Unplug the power connector from the power jack, and then re-plug the connector to restart the AP. Contact our technical support representatives to report this problem, so that the bugs can be static in future firmware versions. If the AP still does not work after restarting, there may be hardware component failures in the AP.
Appendix C: Additional Information C-1: Firmware Upgrade Using Xmodem Upgrade Fig. 62. Xmodem Upgrade. To upgrade the firmware of AP using Xmodem Upgrade over RS232: 1. Power off the AP whose firmware will be upgraded. 2. Connect the managing PC and the AP with an RS232 Null Modem cable. 3. Select the serial port (COM1 or COM2) you use for connecting the device from the Serial port drop-down list and click Connect. 4. Chose the folder in which the firmware files reside by click Browse. 5.
C-2: Distances and Data Rates Important Notice: Maximum distances posted below are actual tested distance thresholds. However, there are many variables such as barrier composition and construction and local environmental interference that may impact your actual distances and cause you to experience distance thresholds far lower than those we post below. IEEE 802.11b Maximum Distance Table Environmental Condition Speed and Distance Ranges 11 Mbps 5.
