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Take Control of Your 802.11n AirPort Network
Make your 802.11n-based AirPort network fast, reliable, and secure!
Find real-world advice from Wi-Fi wizard Glenn Fleishman on setting up the 802.11n models of Apple's AirPort Express, AirPort Extreme, and Time Capsule, with full information about the simultaneous dual-band models introduced in early 2009. You'll get help with all the special networking details, such as how to set the best band and channel for your network, use pre-802.11n base stations and clients without hurting performance, set up complex Internet addressing, share USB disks and printers, solve a variety of problems, and much, much more (see the "More Info" tab below).
Snow Leopard? This ebook was updated for Mac OS X 10.6 Snow Leopard in September 2009! It also thoroughly covers Leopard, and it has info for Windows users, too. See the last question on the FAQ tab below for more details.
More Info
Contents & Intro
What's New
FAQ
Reader Comments
Blog
This 'Take Control' book is a must-have for anyone who needs to quickly and easily set up an AirPort network. —Phil Kearney, "father" of Apple's AirPort product line
If you're trying to solve a particular problem, you can jump in and read the topics in this ebook in any order, but if you start at the beginning, you'll find a primer on important Wi-Fi networking terminology and concepts, and a look at how Apple's 802.11n gear fits into the world of Wi-Fi networking.
With that background, you'll learn how to locate and set up base stations, with diagrams showing common network scenarios—see two examples above on this Web page—and with step-by-step instructions for configuring key Internet sharing and security options and connecting client computers. For those who have funky Internet connections or tricky IP addressing problems, Glenn provides extended advice for creating a working Wi-Fi network.
Glenn also provides real-world steps for important add-ons to a Wi-Fi network, including:
Getting started with a Time Capsule and Time Machine backups, plus thoughts on making an archive so you can have an offsite backup of your Time Capsule drive and what to do if you want to erase the drive
Detailed advice for setting up a USB-based printer and for making connections to the printer work from Macintosh and Windows computers
Help with connecting an Apple TV to your network and advice on how to start syncing it to your computer
Steps and configuration advice for adding a USB-attached drive to a Time Capsule or AirPort Extreme, with important information about how best to allow and configure client access
Tips and setup advice for streaming music from an AirPort Express to your stereo system
Detailed configuration advice for multi-base-station networks
To make your network fly, Glenn helps you:
Make band and channel choices
Combine your old 802.11g network with a new 802.11n network to split traffic and maximize network bandwidth
Extend your network's coverage while handling any interference
Glenn also discusses wireless-network security, noting oft-suggested security approaches that don't work well and explaining how to implement measures that do work well. He covers the new guest networking option in the 2009 models of the AirPort Extreme and Time Capsule.
"If anyone knows about real-world Wi-Fi, it's Glenn Fleishman."
—Mark Frauenfelder, co-founder of bOING bOING
Book Info
265 pages
Version 1.6
Updated 03-Sep-09
5.1 MB download
ISBN: 1933671505
Free sample with Table of Contents, Introduction, Quick Start, and section starts.
About the Author
Glenn Fleishman is a technology journalist based in Seattle, where he lives with his wife and two sons, both of whom are adept at accidentally pressing the Power button on his laptop.
He’s a contributing editor at TidBITS, responsible for much of their Web and publishing infrastructure; a columnist for the Seattle Times on all things Mac related; and a regular contributor to the Economist, Macworld, and Ars Technica. He appears regularly on his local public radio station, KUOW.
Welcome to Take Control of Your 802.11n AirPort Network, version 1.5. This book helps you install and get the most out of an 802.11n Wi-Fi network. It was written by Glenn Fleishman, edited by Tonya Engst, and published by TidBITS Publishing Inc.
Who Needs This Book
If you’re setting up, extending, or retooling a Wi-Fi network with one or more 802.11n base stations from Apple—including the AirPort Extreme, AirPort Express, or Time Capsule—with either Mac OS X 10.5 Leopard or Windows XP or Vista, this book will help you get the fastest network with the least equipment and fewest roadblocks.
Who Doesn't Need This Book
If you're not yet using one of Apple's 802.11n AirPort devices, this book would be worthwhile only for background research if you are considering buying one of those devices. If you use earlier networking hardware on a Mac, consider purchasing Take Control of Your AirPort Network, which covers software and gear released before 2007.
Introduction
Apple introduced integrated wireless networking to the world with AirPort in 1999. Although corporations had already been using forms of wireless networking for warehouse tracking and to connect buildings in large campuses, the cost was high, speeds were low, and complexity was manifest. Other companies were selling similar wireless hardware in 1999, but Apple’s products shot off the shelves due to their relatively low initial price, simple configuration interface, and excellent performance.
AirPort came out of the same approach that allowed Apple to ship the iMac the year before: combining widely available, standard parts in a unique package that provided more value as a whole.
The AirPort Card fit into a special slot in Macintoshes; its stand-alone, central coordinating hub was called the AirPort Base Station. Apple replaced the original AirPort line with AirPort Extreme: first, in 2003 with a somewhat faster flavor (known as 802.11g), then again in 2007, with a substantially faster version (802.11n, at one time more commonly called Draft N). Today, Wi-Fi is built into nearly every Mac.
Despite Apple’s 10-year history with wireless networking and the general excellence of their software and support, setting up a wireless network isn’t always a snap. This book helps you set up a wireless network and offers tips to help save time, improve security, extend range, and enjoy a technical edge when working with AirPort.
Although this book focuses on 802.11n AirPort networks, I also cover compatibility and connections with older hardware, and connecting to 802.11n via Mac OS X, Windows XP, and Windows Vista.
I start with wireless basics, move through installation and configuration, explain how to share printers and hard disks, tell you how to connect to a Wi-Fi network, give advice on extending a network’s range and quality, look at using an AirPort Express’s unique features, and finish with how-to information on security for those who want their AirPort networks safe from freeloaders and intruders.
Quick Start to Your 802.11n AirPort Network
You can read this book from start to finish, and you’ll find that it covers topics like learning about Wi-Fi, unpacking a base station, starting configuration, figuring out the network you want to build, and then configuring that network. More specific cases follow, such as how to add a printer, separating older and newer flavors of Wi-Fi into two separate networks, and securing a network. Use this Quick Start to get an idea of how you might jump into the book if you are at a particular stage in working with your network, and to find more than one path through the material.
Need a quick solution? Flip ahead three pages to the Quick Troubleshooting Guide or see Light Reading to learn what the light on your AirPort base station is trying to tell you. Also, you may especially wish to consult Overcome Interference.
Learn wireless basics:
Get a quick grounding in wireless terminology and technology. See Key Glossary Terms and Learn Wireless Basics.
Familiarize yourself with Apple & Mac Wi-Fi Gear.
Plan your network:
For common configurations, see Set Up a Network, and focus on the diagrams and descriptions at the beginning of: New Network, Single Base Station, Extend a Network via Ethernet, Replace an Existing Base Station, and Extend a Network via Wi-Fi.
For ideas on using the AirPort Express, skim AirPort Express Extras to learn about the features and networking arrangements.
For more advanced possibilities, consult Connect Multiple Base Stations, and pay special attention to the descriptions and diagrams at the start of Add Access Points via Ethernet and Bridge Wirelessly. Also, note that Appendix C covers creating a Software Base Station and Ad Hoc Networking.
To build a network that uses two base stations to separate 2.4 and 5 GHz devices for best performance, read Mix 2.4 GHz and 5 GHz 802.11n Networks.
Set up your base station(s):
Unpack your base station and start down the path of configuring it in Plug In Your Base Station and Get Started. You’ll likely continue in one of these sections:
Learn how to configure a new network with a single base station. See New Network, Single Base Station.
For existing networks, find what you need to Extend a Network via Ethernet or Replace an Existing Base Station.
Separate networks for best performance into different spectrum slices. See Mix 2.4 GHz and 5 GHz 802.11n Networks.
When wireless is the way to go, learn what you need to extend a network using only Wi-Fi. See Extend a Network via Wi-Fi and Bridge Wirelessly.
Hook up a larger network with many base stations. See Connect Multiple Base Stations to build a network that spans a house or office connected wirelessly, or via electrical outlets or Ethernet.
Further configure your network’s LAN settings for fixed addresses or special cases. See Advanced Networking.
Determine the Band, Channel, and Location for your base station, thus making sure your network reaches as far as you want with the bandwidth you need. For help with concepts used in that section, consult The Spectrum Part of Wi-Fi.
Share a printer or a hard drive. See Set Up a Shared USB Printer or Set Up a Shared USB Disk.
Set up Time Machine backups with a Time Capsule base station. Read Work with Time Capsule.
Connect to your base station:
Find out how to connect Macs and systems running Windows to a base station in Connect Your Computers.
Access your network when you’re not physically on it. See Reach Your Network Remotely.
Access hard drives in and connected to your base station via Back to My Mac. See Access a Base Station via MobileMe.
Add music and video:
Use the AirPort Express to stream music. See AirPort Express and AirTunes and Share with Airfoil.
Get jiggy with a video- and audio-streaming set-top box, the Apple TV. See Appendix A: Apple TV and Wi-Fi.
Secure your network:
Decide if you need encryption. Read Likelihood, Liability, and Lost Opportunity.
Avoid security tricks that don’t work. Consult Simple Tricks That Don’t Work.
Apply encryption using the best—and often simplest—method. See Use Built-In Encryption.
If you have a 2009 AirPort Extreme or Time Capsule, you can Set Up Guest Networking.
Learn still more advanced topics:
Find out what the future will bring for end-to-end connections with intermediaries in Explore the Internet’s Future with IPv6.
Stop pulling your hair out over a problem with new firmware you install that doesn’t work. See Revert to Older Firmware.
Get a few details about special configuration options for AirPort Utility that I don’t cover elsewhere by reading the AirPort Pane topic in Appendix B.
Act wonky and fire up Terminal to learn more about your AirPort adapter. Read Appendix E: AirPort Command-Line Utility.
Quick Troubleshooting Guide
If you need quick help, here’s the starting point. I first look at handling a locked-up base station and then give tips for solving a variety of common problems.
Note: Light Reading, a few pages ahead, helps you learn information about a problem by decoding the appearance of a base station’s LED status light.
Reset a Locked-up Base Station
If an AirPort Extreme Base Station, AirPort Express, or Time Capsule neither appears in the AirPort menu as an available network, nor in AirPort Utility as an available base station, try these steps in order:
Check a local connection: Make sure that the computer running AirPort Utility is on the same local network as the base station. Try connecting the computer via Ethernet to one of the base station’s LAN ports. Try AirPort Utility again.
Failing a direct Ethernet connection, try power cycling. Remove the power adapter’s plug from the wall socket or remove the end that plugs into the base station. Wait 10 seconds. Plug it back in, and try to connect via AirPort Utility. Everything may be back to normal.
Warning! You might damage the data on the internal drive by pulling the plug on a Time Capsule. Make sure Time Machine backups or other transfers aren’t in progress when you power cycle a Time Capsule: in the Time Machine menu, choose Stop Backup and wait for it finish; or open the Time Machine preference pane and flip the On switch to Off, and wait until Time Machine is inactive.
Failing power cycling, try a factory reset: This step erases any custom settings you’ve made (I recommend backing up these settings; see Create and Manage Profiles). To reset any of Apple’s three base station models, straighten one end of a paperclip, and with the base station plugged into power, hold down the base station’s reset button with the paperclip end. The reset button is recessed in the rear right of the AirPort Extreme and Time Capsule and next to the audio jack on the AirPort Express; with all three models, the button is beneath the reset symbol, a white arrow reversed out of a gray circle.
Failing a factory reset, try another method to reset the base station: Unplug the base station from power, push in the reset button and hold it down, plug the base station into power, and keep the reset button pressed for at least 20 seconds.
Failing all the above: Call Apple for return instructions.
Printer Problems
Printer on 802.11g part of a mixed legacy/new network won’t print
You’ll need to connect it to your Extreme N or Time Capsule base station. Put Printers in the Right Place explains how.
Can’t print to a USB-connected printer
See Troubleshoot an Unavailable Shared USB Printer.
Other Troubleshooting
Can’t see base station’s network from all Macs
Did you set the base station to use just the 5 gigahertz (GHz) band? Only Mac models released starting in 2005 with 802.11a or 802.11n built in can connect. Or did you set the base station to allow 802.11n-only connections in 2.4 GHz? Only late 2006 and later Macs have 802.11n built in. For more help, read Determine the Band, Channel, and Location.
Further, computers can sometimes temporarily lose their capability to find Wi-Fi networks. Try turning the adapter off and back on—on a Mac, choose Turn AirPort Off from the AirPort menu, and then choose Turn AirPort On. Another common fix is to restart the computer.
Flaky adapter: In some cases, the AirPort adapter may have gone flaky—“flaky” isn’t a technical term, but an apt description. The original AirPort Card and its AirPort Extreme replacement are known to behave erratically the older and more used they become. All Macs sold in the last few years include AirPort Extreme built in, which has turned out to be much more reliable.
Can’t connect to base station’s network; get an error instead
If you can see its network name, try these fixes:
Did you inadvertently set the base station to allow 802.11n-only connections in the 2.4 GHz band? See Connect Your Computers.
Access control may be preventing access. See MAC Address Filtering.
Interference from other networks may be the problem. Consult Eliminate Conflicting Signals.
Error occurs after connecting to a base station with the correct encryption key
You might be using a Mac with the older AirPort Card with a base station set up with WPA2 encryption. See Turning on WPA/WPA2 Personal.
Can’t connect to a base station after selecting it and seeing the summary screen
Are you using Jumbo (9000-byte) frames on your Ethernet adapter? See Jumbo Ethernet Frames Disable AirPort Utility Access.
Firmware update makes base station act erratically
Try to Revert to Older Firmware.
Network works erratically
Another network might be interfering with yours. See Eliminate Conflicting Signals.
Conflicting signals seem to cause network problems
Read Eliminate Conflicting Signals.
What’s New in Version 1.5
Most changes in this version are for Mac OS X 10.6 Snow Leopard:
The Network system preference pane looks slightly different in Snow Leopard.
The AirPort status menu on the menu bar in Snow Leopard has some new features.
Nearly everything else about using AirPort in Leopard and Snow Leopard is identical.
What’s New in Version 1.5
The previous version of this ebook was version 1.0, but we bumped the version number to 1.5 to mark the numerous changes between 1.0 and 1.5. Here’s a summary of the most important changes:
Added coverage of the March 2009 models of the AirPort Extreme Base Station and Time Capsule. These new base stations have substantial hardware changes and a few software changes, including:
Two internal radios instead of one, allowing two networks to function simultaneously, one in each of the two unlicensed bands used by Wi-Fi.
Support for guest networking, in which a separately named virtual network lets guests connect to the Internet, while keeping them from accessing to the local network. The guest network may be password protected. See Set Up Guest Networking for full details.
Remote access via Back to My Mac to the base station, providing access to any attached or internal hard drives, and permitting remote configuration of the base station via AirPort Utility. Read Access a Base Station via MobileMe for directions. (This feature is also available via a firmware update to all 802.11n base stations released in 2007 or later.) To learn more about the new base station models, consult AirPort Base Station Models.
Extend a Network via Wi-Fi is reworked for enhanced clarity and to explain how the Wireless Distribution System (WDS) differs in 802.11n base stations from previous generations of gear.
A new section, Light Reading, decodes what the light on your base station is trying to tell you.
The section about setting a base station’s spectrum is now called Determine the Band, Channel, and Location, and it has been revised: advanced background information was expanded and moved to the new Appendix D: Channels Explained, and various changes were made to reflect the new simultaneous dual-band products, which don’t require that you choose a band.
How This Book Differs from Earlier Editions
This book is based largely on two previous books: Take Control of Your AirPort Network (2005) and Take Control of Your 802.11n AirPort Extreme Network (2007). The former book covered 802.11g AirPort networking; the latter, the newer 802.11n (now more commonly called Draft N) networks. Both books focused on using Mac OS X 10.4 Tiger.
This new book covers much of the same material, but in slightly to extremely different ways. Apple thoroughly revised the new AirPort Utility base station configuration program between the release of its second version of the AirPort Extreme Base Station with Draft N (August 2007) and the release of Time Capsule (February 2008).
These changes meant reworking much of the earlier part of the book explaining how to use the Assist Me mode in AirPort Utility; in the process, I split my advice into scenarios that cover the different kinds of networks you might be building or updating. This should make basic configuration easier, as well as help you easily find help if you return to the book to configure or add base stations in the future, or to set up multiple networks in different places.
I’ve also overhauled the manuscript to focus on Mac OS X 10.5 Leopard and network troubleshooting issues, while updating it for all the latest models of 802.11n base stations.
Further, I’ve added more information about IPv6, the next-generation Internet numbering standard, which is starting to have practical applications, and which can be used quite easily with all of Apple’s current Wi-Fi gear, and Mac OS X since version 10.3 Panther.
Does this ebook talk about the new AirPort Extreme and Time Capsule that came out in March of 2009?
Yes! It also notes the Time Capsule's June 2009 increase in disk capacity.
Can I attach a hard drive to an AirPort Express?
P.F. wrote in to ask: "I have an Airport Express (purchased April 08). I have tried to mount an external drive as an AirDisc, with no success. Does your book take me through the steps?"
Here is Glenn's reply: "The AirPort Express can't handle an external hard drive. Only the AirPort Extreme and Time Capsule base stations can share hard drives their USB ports. The Express supports a single printer, only. See: http://www.apple.com/airportexpress/features/printing.html. Sorry for the bad news. While it seems like Apple might be being petty at not including hard drive support in the Express, I have become fairly confident that they keep the price low on that unit while including features nobody else does (dual-band support, etc.) by having a quite low-powered processor. That processor likely can't handle the demands of communicating with a hard drive while operating as a base station. The processor (or there may be multiples) in the higher-end base stations are much more capable."
Do you have an ebook that focuses on older Apple base stations?
Take Control of Your AirPort Network is still available, and although its descriptions of how to network 802.11b and 802.11g gear remain useful, as I write this text in June of 2009, I'm noting that the ebook doesn't discuss Mac OS X 10.5 Leopard and its coverage of AirPort Utility is becoming dated. Even so, the ebook remains available for sale, and we would, of course, allow you to return the ebook were you to buy it and find it too obsolete to be useful.
Operating Systems Covered in This Book
The AirPort Extreme Base Station comes with utility software, AirPort Utility, that runs on Mac OS X and on Windows XP and Vista. This book assumes that readers might run that software on a Macintosh or on a Windows computer. The book also covers connecting to an AirPort Extreme Base Station (and to any shared disks or printers on the base station) from Mac OS X 10.4 Tiger, 10.5 Leopard, 10.6 Snow Leopard, Windows XP, and Windows Vista.
Ask a Question
Feel free to ask us if you have a question about this book!
Phil Kearney, "father" of Apple's AirPort product line, writes:
This "Take Control" book is a must-have for anyone who needs to quickly and easily set up an AirPort network. It is a clean and concise guide to get you past any stumbling blocks you may encounter in the process of configuring your wireless network. Even the more advanced chapters and topics will be a great help to anyone who designs and installs 802.11 networks for a living.
David Travis, a reader who ended up with a blazingly fast network, writes:
I bought the book because I'd just purchased a Time Capsule and I wanted to know (a) if my old Graphite Base Station was now a white elephant and (b) if the older Macs on my home network would prevent me from getting top speed from my new Time Capsule. Glenn's book showed be how to use Airport Utility to set up a 2.4 GHz and a 5 GHz network in parallel, answering both questions. Thanks to that guidance, and the tip about OpenDNS, I now have a blazingly fast Internet connection.
Reader with a zero config problem writes:
Your book saved the day for me. In fact, it saved several days. A Windows laptop connected to my AirPort network via a WEP connection suddenly failed to recognize the AirPort signal. After 2 wasted days of troubleshooting, I thought to consult your ebook.
It described precisely the problem I was having and advised me to restart 'Wireless Zero Configuration.' I was up and running with about two mouse clicks! Many thanks for your on-target advice. I won't be so slow to consult your material in the future. —W.P.
Send Us Your Comments!
How could we not publish such kind words? If you'd like to send us your comments (good or bad, though we hope they're all good), just click the Feedback link on the cover of your copy of the ebook. Be sure to let us know if we can publish your comment. Thanks!
Update Plans
September 2009 -- The current version of this ebook, version 1.6, is updated for Mac OS X 10. 6 Snow Leopard and for all AirPort base station models released so far in 2009. At this time we have no immediate plans to update the ebook.
Reader Patrick O. recently wrote in asking, "Is there some way to extend the range of the guest feature of the AirPort Extreme N Dual Band models? I can extend the main network, but the guest network resists all efforts, and some online searches say it cannot be done."
Glenn replied, "Cannot be done, sorry. This is a limitation in how Apple has created the guest network, which is to create a virtual SSID, a kind of alternate but software-created network name."
Thanks to Patrick for asking, and I hope this blog post saves someone else from spending a lot of time hunting for a non-existent option.
Yesterday, Apple introduced a small set of changes with big effects to the AirPort Extreme Base Station and Time Capsule:
Apple added more antennas to the existing multiple-in, multiple-out (MIMO) array in both of these devices, moving from a 2x2 array, with two receive and two transmit antennas, to a 3x3 array, with three each for sending and receiving. The new 3x3 array dramatically boosts network throughput as you get farther from a base station. Instead of seeing data rates drop off—I describe in the book how to monitor those rates—the new base station models will maintain the same speed for greater distances. Apple says the boost is as much as 50 percent over previous models, which conforms to what Wi-Fi chipmakers have said. The additional antennas also increase range, which Apple says could be as much as 25 percent farther from these new base stations than from preceding models. This is, alas, a change to the physical chip and antenna elements in the devices, so Apple can't put the improvements into a new firmware version.
Apple also said that Time Machine backups from Snow Leopard to the new Time Capsule model have been sped up by as much as 60 percent; there's a lot of inefficiency in Time Machine networked backups, so there's a lot of room to improve. If this speed boost isn't hardware based, it could be found in a future firmware release, but it may involve better network processors or a new central processor, and thus be unavailable to older Time Capsules.
Glenn Fleishman is known for his infectious enthusiasm for all things AirPort, and he certainly lived up to that reputation with his speedy work updating his popular ebook Take Control of Your 802.11n AirPort Network to cover Mac OS X 10.6 Snow Leopard. The ebook still covers Mac OS X 10.5 Leopard, and it still has notes about older versions of Mac OS X (and Windows XP and Vista) where appropriate, such as when describing how to connect to an AirPort-attached USB printer. The 265-page ebook remains priced at $15.
This update cleans up a few loose ends, such as the fact that the Time Capsule no longer has a 500 GB model and instead comes in 1 TB and 2 TB sizes. The main point of the update, however, is to add Snow Leopard information. This involved a number of small wording changes, some new screenshots, and a major revision of the text that discusses the AirPort menu in the menu bar. That's key because Snow Leopard makes a few subtle changes, and Option-clicking to open the menu in Snow Leopard reveals much more useful information about nearby networks than was present in Leopard.
If you already own version 1.x of Take Control of Your 802.11n AirPort Network, you can get a free update; open your PDF to page 1 and click Check for Updates. If you own one of Glenn's previous AirPort ebooks, you can access a discounted update via Check for Updates.
The IEEE, the engineering group that develops and shepherds the 802.11 family of specifications, has moved the 802.11n standard out of lower-level committees. The standard, started several years ago, and called Draft N since the standard wasn't precisely finished even though details were fundamentally finalized, will be fully ratified later this year.
One of the interesting things about Apple's AirPort networking hardware is that it often evolves in subtle ways that Apple doesn't call out, making books like Glenn Fleishman's Take Control of Your 802.11n AirPort Network all the more useful. Plus, since many of us add newer AirPort devices to networks that already rely on older AirPort hardware, our wireless networks are becoming all the more complex, even as setting up a very simple one becomes easier. That's the theme of this MacVoices podcast discussion with host Chuck Joiner, so if you're interested in learning about the new features Glenn explains in Take Control of Your 802.11n AirPort Network and the ways that Glenn and Take Control publisher Adam Engst revised their Take Control of Your Wi-Fi Security, listen to this podcast.
A long-time TidBITS reader was twittering yesterday about feeling frustrated with the iPhone still lacking 802.11n, because he wanted to connect his iPhone to an 802.11n-only home network. Glenn Fleishman twittered back with a link to an article Does the iPhone Need 802.11n? that Glenn wrote for the Wi-Fi Net News Web site. The article explains likely reasons why Apple chose not to include 802.11n in the iPhone and speculates that an upcoming single-stream 802.11n technology might find its way into the iPhone and similar devices.
Glenn Fleishman is a technology journalist based in Seattle, where he lives with his wife and two sons, both of whom are adept at accidentally pressing the Power button on his laptop.
He’s a contributing editor at