Apple AirPort Networks
1 2 Contents Chapter 1 3 5 6 6 6 6 Getting Started Configuring an Apple Wireless Device for Internet Access Using AirPort Utility Extending the Range of Your AirPort Network Sharing a USB Hard Disk Connected to an AirPort Extreme Base Station or Time Capsule Printing with an Apple Wireless Device Sharing Your Computer’s Internet Connection Chapter 2 9 9 10 11 AirPort Security Security for AirPort Networks at Home Security for AirPort Networks in Businesses and Classrooms Wi-Fi Protected Access (WPA)
1 Getting Started 1 AirPort offers the easiest way to provide wireless Internet access and networking anywhere in the home, classroom, or office. AirPort is based on the latest Institute of Electrical and Electronics Engineers (IEEE) 802.11n draft specification and provides fast and reliable wireless networking in the home, classroom, or small office. You can enjoy data transfer rates of up to five times faster than data rates provided by the 802.11g standard and more than twice the network range.
Note: When the features discussed in this document apply to the AirPort Extreme Base Station, AirPort Express, and Time Capsule, the devices are referred to collectively as Apple wireless devices. With an AirPort Extreme Base Station or a Time Capsule, you can connect a USB hard disk so that everyone on the network can back up, store, and share files. Every Time Capsule includes an internal AirPort disk, so you don’t need to connect an external one.
You can set up an Apple wireless device and connect to the Internet wirelessly in minutes. But because Apple wireless devices are flexible and powerful networking products, you can also create an AirPort network that does much more. If you want to design an AirPort network that provides Internet access to non-AirPort computers via Ethernet, or take advantage of some of your wireless device’s more advanced features, use this document to design and implement your network.
Set up your Apple wireless device manually using AirPort Utility when:  You want to provide Internet access to computers that connect to the wireless device using Ethernet  you’ve already set up your device, but you need to change one setting, such as your account information  You need to configure advanced settings such as channel frequency, advanced security options, closed networks, DHCP lease time, access control, WAN privacy, power controls, or port mapping or other options For instructions on using
You can share your Internet connection as long as your computer is connected to the Internet. If your computer goes to sleep or is restarted, or if you lose your Internet connection, you need to restart Internet sharing. To start Internet sharing on a computer using Mac OS X v10.5 or later: 1 Open System Preferences and click Sharing. 2 Choose the port you want to use to share your Internet connection from the “Share your connection using” pop-up menu.
To start Internet sharing on a computer using Windows: 1 Open Control Panel from the Start menu, and then click “Network and Internet.” 2 Click “Network and Sharing Center.” 3 Click “Manage network connections” in the Tasks list. 4 Right-click the network connection you want to share, and then select Properties. 5 Click Sharing and then select “Allow other network users to connect through this computer’s Internet connection.
2 AirPort Security 2 This chapter provides an overview of the security features available in AirPort. Apple has designed its wireless devices to provide several levels of security, so you can enjoy peace of mind when you access the Internet, manage online financial transactions, or send and receive email. The AirPort Extreme Base Station and Time Capsule also include a slot for inserting a lock to deter theft.
Password Protection and Encryption AirPort uses password protection and encryption to deliver a level of security comparable to that of traditional wired networks. Users can be required to enter a password to log in to the AirPort network. When transmitting data and passwords, the wireless device uses up to 128-bit encryption, through either Wi-Fi Protected Access (WPA), WPA2, or Wired Equivalent Privacy (WEP), to scramble data and help keep it safe. If you’re setting up an 802.
RADIUS Support The Remote Authentication Dial-In User Service (RADIUS) makes securing a large network easy. RADIUS is an access control protocol that allows a system administrator to create a central list of the user names and passwords of computers that can access the network. Placing this list on a centralized server allows many wireless devices to access the list and makes it easy to update. If the MAC address of a user’s computer (which is unique to each 802.
The EAP protocol known as TLS (Transport Layer Security) presents a user’s information in the form of digital certificates. A user’s digital certificates can comprise user names and passwords, smart cards, secure IDs, or any other identity credentials that the IT administrator is comfortable using.
WPA and WPA2 Enterprise WPA is a subset of the draft IEEE 802.11i standard and effectively addresses the wireless local area network (WLAN) security requirements for the enterprise. WPA2 is a full implementation of the ratified IEEE 802.11i standard. In an enterprise with IT resources, WPA should be used in conjunction with an authentication server such as RADIUS to provide centralized access control and management.
3 AirPort Network Designs 3 This chapter provides overview information and instructions for the types of AirPort Extreme networks you can set up, and some of the advanced options of AirPort Extreme. Use this chapter to design and set up your AirPort Extreme network. Configuring your Apple wireless device to implement a network design requires three steps: Step 1: Setting Up the AirPort Extreme Network Computers communicate with the wireless device over the AirPort wireless network.
Using AirPort Utility To set up and configure your computer or Apple wireless device to use AirPort Extreme for basic wireless networking and Internet access, use AirPort Utility and answer a series of questions about your Internet settings and how you would like to set up your network. 1 Open AirPort Utility, located in the Utilities folder in the Applications folder on a Mac, or in Start > All Programs > AirPort on a Windows computer.
Select from the following checkboxes: Â Select “Check for Updates when opening AirPort Utility” to automatically check the Apple website for software and firmware updates each time you open AirPort Utility. Â Select the “Check for updates” checkbox, and then choose a time interval from the pop-up menu, such as weekly, to check for software and firmware updates in the background. AirPort Utility opens if updates are available.
If you can’t open the wireless device settings: 1 Make sure your network and TCP/IP settings are configured properly. On a computer using Mac OS X, select AirPort from the network connection services list in the Network pane of System Preferences. Click Advanced, and then choose Using DHCP from the Configure IPv4 pop-up menu in the TCP/IP pane. On a computer using Windows, right-click the wireless connection icon that displays the AirPort network, and choose Status.
3 Choose Base Station > Manual Setup and enter the password if necessary. The default device password is public. You can also double-click the name of the wireless device to open its configuration in a separate window. When you open the manual setup window, the Summary pane is displayed. The summary pane provides information and status about your wireless device and network.
If the wireless device reports a problem, the status icon turns yellow. Click Base Station Status to display the problem and suggestions to resolve it. Wireless Device Settings Click the AirPort button, and then click Base Station or Time Capsule, depending on the device you’re setting up, to enter information about the wireless device. Give the Device a Name Give the device an easily identifiable name.
Set Device Options Click Base Station Options and set the following: Â Enter a contact name and location for the wireless device. The name and location are included in some logs the device generates. The contact and location fields may be helpful if you’ve more than one wireless device on your network. Â Set status light behavior to either Always On or Flash On Activity. If you choose Flash On Activity, the device status light blinks when there is network traffic.
Choosing the Radio Mode Choose 802.11a/n - 802.11b/g from the Radio Mode pop-up menu if computers with 802.11a, 802.11n, 802.11g, or 802.11b wireless cards will join the network. Each client computer will connect to the network and transmit network traffic at the highest possible speed. Choose 802.11n - 802.11b/g if only computers with 802.11n, 802.11b, or 802.11g compatible wireless cards will join the network. Note: If you don’t want to use an 802.
 WPA/WPA2 Personal: Choose this option to protect your network with Wi-Fi Protected Access. You can use a password between 8 and 63 ASCII characters or a Pre-Shared Key of exactly 64 hexadecimal characters. Computers that support WPA and computers that support WPA2 can join the network. Choose WPA2 Personal if you want only computers that support WPA2 to join your network.
Setting Additional Wireless Options Use the Wireless Options pane to set the following: Â 5 GHz network name: Provide a name for the 5 GHz segment of the dual-band network if you want it to have a different name than the 2.4 GHz network. Â Country: Choose the country for the location of your network from the Country pop-up menu. Â Multicast rate: Choose a multicast rate from the pop-up menu.
Setting up a Guest Network Click Guest Network and then enter the network name and other options for the guest network. When you set up a guest network, a portion of your connection to the Internet is reserved for “guests”, wireless clients that can join the guest network and connect to the Internet without accessing your private network.
What It Looks Like to Ethernet port 2.4 or 5 GHz Time Capsule < Ethernet WAN port DSL or cable modem to Internet How It Works  The Apple wireless device (in this example, a Time Capsule) connects to the Internet through its Internet WAN (<) connection to your DSL or cable modem.  Computers using AirPort or computers connected to the wireless device’s Ethernet LAN port (G) connect to the Internet through the device.
What to Do If you’re using AirPort Utility to assist you with configuring the Apple wireless device for Internet access: 1 Open AirPort Utility, located in the Utilities folder in the Applications folder on a Mac, or in Start > All Programs > AirPort on a Windows computer. 2 Follow the onscreen instructions and enter the settings you received from your service provider to connect to the Internet, and then set up the device to share the Internet connection with computers on the network.
 If you chose PPPoE, your ISP provides your IP address automatically using DHCP. Contact your service provider for the information you should enter in these fields. Use this pop-up menu if you need to adjust the speed of the Ethernet WAN port. If your service provider asks you for the MAC address of your wireless device, use the address of the Ethernet WAN port (<), printed on the label on the bottom of the device.
If you configure TCP/IP using DHCP, choose Using DHCP from the Configure IPv4 pop-up menu. Your IP information is provided automatically by your ISP using DHCP. Your service provider may require you to enter information in these fields. 5 If you chose PPPoE from the Connect Using pop-up menu, enter the PPPoE settings your service provider gave you. Leave the Service Name field blank unless your service provider requires a service name.
If you’re connecting to the Internet through a router that uses PPPoE to connect to the Internet, and your wireless device is connected to the router via Ethernet, you do not need to use PPPoE on your device. Choose Ethernet from the Connect Using pop-up menu in the Internet pane, and deselect the “Distribute IP addresses” checkbox in the Network pane. Because your router is distributing IP addresses, your wireless device doesn’t need to.
 Enter Domain Name System (DNS) server addresses and a specific domain name your wireless device accesses when you connect to the Internet. 7 Click the Network button and configure how the device will share its Internet access with AirPort and Ethernet computers. If you chose Ethernet from the Connect Using pop-up menu, choose how your device will share the Internet connection from the Connection Sharing pop-up menu.
 If you don’t want your wireless device to share its IP address, choose “Off (Bridge Mode).” If you set up your device in bridge mode, AirPort computers have access to all services on the Ethernet network, and the device does not provide Internet sharing services. See “You’re Using an Existing Ethernet Network” on page 37 for more information about setting up your wireless device as a bridge.
 To provide specific IP addresses to specific computers on your wireless network, click the Add (+) button below the DHCP Reservations list, and follow the onscreen instructions to name the reservation and reserve the address by MAC address or DHCP client ID. If you choose MAC address, click Continue and enter the MAC address and specific IP address. Next you can set NAT options for the network. Click NAT.  You can set up a default host on your network.
You can also set up port mapping. To ensure that requests are properly routed to your web, AppleShare, or FTP server, or a specific computer on your network, you need to establish a permanent IP address for the server or computer, and provide “inbound port mapping” information to the Apple wireless device. See “Directing Network Traffic to a Specific Computer on Your Network (Port Mapping)” on page 49.
Next, choose DHCP from the Configure IPv4 pop-up menu. b If you enabled a DHCP server when you set up the wireless device’s network, and the client computer is using Ethernet, select Ethernet in the network connection services list, and then choose Using DHCP from the Configure pop-up menu.
c If you selected “Distribute a range of IP addresses” when you set up the wireless device’s network, you can provide Internet access to client computers using Ethernet by setting the client IP addresses manually. Select Ethernet in the network connection services list, and then choose Manually from the Configure pop-up menu. Enter the IP and router addresses from the range your device is providing. Enter the DNS and Search Domain addresses if necessary.
5 Click Internet Protocol Version 4 (TCP/IPv4), and then click Properties. Â If you chose “Share a public IP address” in the Network pane of AirPort Utility, select “Obtain an IP address automatically.” Â If you chose “Distribute a range of IP addresses” when you set up the wireless device’s network, you can provide Internet access to client computers by setting the client IP addresses manually. Select “Use the following IP address.
You’re Using an Existing Ethernet Network You can use AirPort Utility to easily set up the Apple wireless device for Internet access through an existing Ethernet network that already has a router, switch, or other network device providing IP addresses. Use the manual setup features of AirPort Utility if you need to adjust optional advanced settings. What It Looks Like to Ethernet port 2.
What to Do If you’re using AirPort Utility to help you set up an Apple wireless device on an existing Ethernet network: 1 Open AirPort Utility, located in the Utilities folder in the Applications folder on a Mac, or in Start > All Programs > AirPort on a Windows computer. 2 Click Continue and follow the onscreen instructions to connect to your local area network (LAN).
If your IP address is provided by DHCP, choose Using DHCP from the Configure IPv4 pop-up menu. 5 Choose Off (Bridge Mode) from the Connection Sharing pop-up menu. Your wireless device “bridges” the Ethernet networks Internet connection to computers connected to the device wirelessly or by Ethernet. See “Setting Up Client Computers” on page 33 for information about how to set up client computers to connect to the Ethernet network.
Connecting Additional Devices to Your AirPort Extreme Network Connect a USB printer to the USB port of your Apple wireless device (in this example, a Time Capsule) and everyone on the network can print to it. Connect a USB hub to the USB port of an AirPort Extreme Base Station or a Time Capsule, and then connect a hard disk and a printer so everyone on the network can access them. If you connect a Time Capsule, you can use Time Machine in Mac OS X Leopard (v10.5.
Using Apple TV on Your AirPort Extreme Network to Play Content from iTunes When you connect Apple TV to your AirPort Extreme network wirelessly, or using Ethernet, and then connect Apple TV to your widescreen TV, you can enjoy your favorite iTunes content including movies, TV shows, music, and more. (See the documentation that came with your Apple TV for instructions setting it up.) to Ethernet port 2.4 or 5 GHz Time Capsule 2.
Setting Up Roaming Several AirPort Extreme Base Stations or Time Capsules can be set up to create a single wireless network. Client computers using AirPort can move from device to device with no interruption in service (a process known as roaming). To set up roaming: 1 Connect all of the AirPort Extreme Base Stations and Time Capsules to the same subnet on your Ethernet network. 2 Give each device a unique name. 3 Give each device the same network name and password.
Extending the Range of an 802.11n Network Extending the range of an 802.11n network is simpler if you’re connecting another 802.11n device. Connecting two Apple 802.11n wireless devices makes the WDS setup process more straightforward. To extend the range of an 802.11n network: 1 Open AirPort Utility and select the device that will connect to the Internet. See the previous sections of this document for instructions about setting up your wireless device, depending on your Internet connection.
8 Click Update to update the device with new network settings. Controlling the Range of Your AirPort Network You can also shorten the range of your AirPort network. This might be useful if you want to control who has access to the network by restricting the range to a single room, for example. To shorten the range of your AirPort network: 1 Open AirPort Utility (in the Utilities folder in the Applications folder on a Macintosh computer, or in Start > All Programs > AirPort on a computer using Windows).
Keeping Your Network Secure Your network is protected by the password you assign to it. However, you can take additional steps to help keep your network secure. Networks managed by Simple Network Management Protocol (SNMP) may be vulnerable to denial-of-service attacks. Similarly, if you configure your wireless device over the WAN port, it may be possible for unauthorized users to change network settings.
Personal mode is for the home or small office network and can be set up and managed by most users. Personal mode does not require a separate authentication server. Network users usually only need to enter a user name and password to join the network. Note: If you change an existing WDS network from WEP to WPA, you’ll need to reset the wireless devices and set up your network again. For information about resetting your Apple wireless device, see the documentation that came with it.
Setting Up Access Control Access control lets you specify which computers can send or receive information through the wireless device to the wired network. Each wireless-enabled computer has a unique MAC address. You can restrict access by creating an access control list that includes only the MAC addresses for computers you want to access your wired network. To find the MAC address (AirPort ID) of your computer’s AirPort Card, click the AirPort button in the Network pane of System Preferences.
 If you choose RADIUS, enter the type of RADIUS service, the RADIUS IP addresses, shared secret, and primary port for the primary RADIUS server. Enter the information for the secondary RADIUS server if there is one. Check with the server administrator if you don’t have that information. Important: AirPort access control prevents computers that aren’t on the access control list from accessing the AirPort network.
5 Enter the IP address, port, and shared secret (or password) for the primary and secondary servers. See the RADIUS documentation that came with your server, or check with the network administrator for more information on setting up the RADIUS server. The access control list and RADIUS work together.
If you’re using a web, AppleShare, or FTP server on your AirPort Extreme network, other computers initiate communication with your server. Because the Apple wireless device has no table entries for these requests, it has no way of directing the information to the appropriate computer on your AirPort network.
Type any additional information you need in the text fields. To use port mapping, you must configure TCP/IP manually on the computer that is running the web, AppleShare, or FTP server. You can also set up a computer as a default host to establish a permanent IP address for the computer and provide inbound port mapping information to the AirPort Extreme Base Station or AirPort Express. This is sometimes known as a DMZ and is useful when playing some network games or video conferencing.
3 Enter the IP address of the computer that will receive the logs in the Syslog Destination Address field. 4 Choose a level from the Syslog Level pop-up menu. You need to assign a Network Time Protocol (NTP) server for each wireless device, so the log information will contain the accurate time of the status logs.
Setting up IPv6 IPv6 is a new version of Internet Protocol (IP). IPv6 is currently used primarily by some research institutions. Most computers do not need to set up or use IPv6. The primary advantage of IPv6 is that it increases the address size from 32 bits (the current IPv4 standard) to 128 bits. An address size of 128 bits is large enough to support billions and billions of addresses. This allows for more addresses or nodes than are currently available.
Sharing and Securing USB Hard Disks on Your Network If you connect a USB hard disk to your AirPort Extreme Base Station or Time Capsule, computers connected to the network—both wireless and wired, Mac and Windows— can use it to back up, store, and share files. If you’re using a Time Capsule, you don’t need to connect a hard disk to it. Every Time Capsule includes an internal AirPort disk. 2.4 or 5 GHz AirPort Extreme USB hard disk DSL or cable modem 2.
Using a Time Capsule in Your Network If you’re using a Time Capsule and a computer with Mac OS X Leopard (v10.5.2 or later), you can use Time Machine to automatically back up all of the computers on the network that are using Leopard. Other Mac computers and Windows computers can access the Time Capsule’s internal AirPort disk to back up, store, and share files. And because every Time Capsule is also a full-featured 802.
 On a computer using Windows, install Bonjour for Windows from AirPort Utility CD, and follow the onscreen instructions to connect to the printer. You can change the name of the printer from the default name to one you choose. To change the name of your USB printer: 1 Open AirPort Utility, select your device, and then choose Base Station > Manual Setup, or double-click the device icon to open its configuration in a separate window.
Solving Problems If you have trouble connecting to the Internet with any AirPort Extreme network design, try the following: On a computer using Mac OS X: Â Make sure the wireless device is connected to the Internet. The computers on your AirPort network cannot connect to the Internet if your device is not connected to the Internet. Â Check your Internet connection using your computer. If you can’t connect with your computer, the problem may be with your Internet connection. Â On a Mac using Mac OS X v10.
 Make sure that the computer has joined the AirPort network created by your wireless device.  Restart your computer. This renews the IP address you receive from the wireless device. The IP addresses should be in the range of 10.0.1.2 to 10.0.1.200, 172.16.1.2 to 172.16.1.200, or 192.168.1.2 to 192.168.1.200 depending on the address scheme the device uses.
4 Behind the Scenes 4 This chapter defines terms and concepts used to discuss computer networks. Use it as a reference to help you understand what is taking place behind the scenes of your AirPort wireless network. Basic Networking Packets and Traffic Information travels across a network in chunks called packets. Each packet has a header that tells where the packet is from and where it’s going, like the address on the envelope when you send a letter.
So, your computer also has an Internet Protocol (IP) address that defines exactly where and in what network it’s located. IP addresses ensure that your local Ethernet network receives only the traffic intended for it. Like the hierarchical system used to define zip codes, street names, and street numbers, IP addresses are created according to a set of rules, and their assignment is carefully administered. The hardware address is like your name; it uniquely and permanently identifies you.
Using the Time Capsule This section describes the different network interfaces of the Time Capsule and describes the functions it can provide. Time Capsule Interfaces To use your Time Capsule, you configure how its networking interfaces will be used. The Time Capsule has five hardware networking interfaces: Â AirPort interface: The AirPort interface creates an AirPort network for AirPortenabled computers to join. The Time Capsule can provide IP services such as DHCP and NAT using this interface.
 Audio (-) interface: Use the analog and optical digital audio stereo mini-jack to connect an AirPort Express to a home stereo or powered speakers. Status light AC plug adapter d USB port G Ethernet port ∏ Reset button - Line Out port (Analog and optical digital audio mini-jack) Apple Wireless Device Functions  Bridge: Each Apple wireless device is configured by default as a bridge between the wireless AirPort network and the wired Ethernet network.
Items That Can Cause Interference with AirPort The farther away the interference source, the less likely it is to cause a problem. The following items can cause interference with AirPort communication:  Microwave ovens  DSS (Direct Satellite Service) radio frequency leakage  The original coaxial cable that came with certain types of satellite dishes. Contact the device manufacturer and obtain newer cables.
10Base-T The most common cabling method for Ethernet. 10Base-T conforms to IEEE standard 802.3. It was developed to enable data communications over unshielded twisted pair (telephone) wiring at speeds of up to 10 megabits per second (Mbps) up to distances of approximately 330 feet on a network segment. 10/100Base-T A networking standard that supports data transfer rates up to 100 Mbps. Because it is 10 times faster than Ethernet, it is often referred to as Fast Ethernet.
backbone The central part of a large network that links two or more subnetworks. The backbone is the primary data transmission path on large networks such as those of enterprises and service providers. A backbone can be wireless or wired. bandwidth The maximum transmission capacity of a communications channel at any point in time. Bandwidth, usually measured in bits per second (bps), determines the speed at which information can be sent across a network.
channel One portion of the available radio spectrum that all devices on a wireless network use to communicate. Changing the channel on the access point/router can help reduce interference. client Any computer or device connected to a network that requests files and services (files, print capability) from the server or other devices on the network. The term also refers to end users. DHCP Dynamic Host Configuration Protocol.
firewall A system of software and/or hardware that resides between two networks to prevent access by unauthorized users. The most common use of a firewall is to provide security between a local network and the Internet. Firewalls can make a network appear invisible to the Internet and can block unauthorized and unwanted users from accessing files and systems on the network.
LAN Local area network. A system of connecting PCs and other devices within the same physical proximity for sharing resources such as an Internet connections, printers, files, and drives. When Wi-Fi is used to connect the devices, the system is known as a wireless LAN or WLAN. See WAN. MAC address Media Access Control address. A unique hardware number that identifies each device on a network. A device can be a computer, printer, and so on. A MAC address is also known as an AirPort ID.
roaming (Wi-Fi) The ability to move from one area of Wi-Fi coverage to another with no loss in connectivity (hand-off ). router A wireless router is a device that accepts connections from wireless devices to a network, includes a network firewall for security, and provides local network addresses. See hub. server A computer that provides resources or services to other computers and devices on a network. Types of servers include print servers, Internet servers, mail servers, and DHCP servers.
WEP Wired equivalent privacy. The original security standard used in wireless networks to encrypt the wireless network traffic. See WPA, Wireless local area network. Wi-Fi A term developed by the Wi-Fi Alliance to describe wireless local area network (WLAN) products that are based on the Institute of Electrical and Electronics Engineers. Wi-Fi Certified The certification standard designating IEEE 802.
WPA2 - Enterprise Wi-Fi Protected Access 2 - Enterprise. The follow-on wireless security method to WPA that provides stronger data protection for multiple users and large managed networks. It prevents unauthorized network access by verifying network users through an authentication server. See WPA2. WPA2 - Personal Wi-Fi Protected Access 2 - Personal. The follow-on wireless security method to WPA that provides stronger data protection and prevents unauthorized network access for small networks.
www.apple.com/airportextreme www.apple.com/airport © 2009 Apple Inc. All rights reserved. Apple, the Apple logo, AirPort, AirPort Extreme, AppleShare, AppleTalk, Back to My Mac, Bonjour, Mac, and Mac OS are trademarks of Apple Inc., registered in the U.S. and other countries. AirPort Express, AirTunes, Time Capsule, and Time Machine are trademarks of Apple Inc. Other product and company names mentioned herein may be trademarks of their respective companies.