Bluetooth breaks through

Picture this: On your way out the door for a business trip, you drop your cell phone and headset into your briefcase. In the cab on the way to the airport, you open your PowerBook and — without hooking up or even touching your phone — dial up your ISP to check your e-mail. Remembering that it’s your daughter’s birthday, you don the headset and recite her phone number into the microphone. Moments later, you’re connected and discussing birthday plans — all within the confines of the cab, and all without wires.

How, you ask? Meet Bluetooth, the new wireless technology quickly being adopted by Apple Computer Inc. And even though you can’t do everything in this scenario yet, it provides a small example of the potential that Bluetooth brings to the Mac.

Although it has been built into many devices in Japan and Europe for several years, Bluetooth has been slow to catch on in the United States. But with the recent announcement of a Bluetooth USB adapter and accompanying “technology preview” software, Apple has started the ball rolling — and piqued the interest of the Mac community. Come see what all the fuss is about.

What Is Bluetooth?

Bluetooth is a protocol that allows short-range communication among computers, cell phones, printers, keyboards, mice, and other electronic devices. Unlike AirPort, Apple’s technology for wireless networking, Bluetooth’s purpose is to replace the cables between your Mac and its peripherals — usually USB devices.


All Bluetooth-enabled products require a tiny built-in radio transceiver. Devices can usually communicate with each other at distances of up to 30 feet. With a clear line of sight, the range can increase. But just as a good path can benefit Bluetooth, large, solid obstacles can block the signal, significantly reducing transmission range.


Bluetooth’s maximum throughput is 1 megabit per second (Mbps) — compare that with 11 Mbps for AirPort; 12 Mbps for USB; 400 Mbps for FireWire; and either 10 Mbps, 100 Mbps, or 1,000 Mbps (1 Gbps) for Ethernet. All of these require overhead, however, that decreases the actual bandwidth available; with Bluetooth, the usable data throughput is about 650 kilobits per second (Kbps) or 80 kilobytes per second (KBps). My Mac-to-Mac file transfer using Bluetooth topped out at around 63 KBps — and that was at very close range with no obstacles. When my two Macs were separated by about ten feet, with a chair and a Power Mac G4 in the way, the rate dropped to 50 KBps. (In a similar test, AirPort was about four-and-a-half times as fast as Bluetooth — see our review of the AirPort card.


Bluetooth changes the way devices interact. Currently, even with AirPort in the picture, the resources to which your Mac can gain access are fixed, stationary, and tied to a network. Sure, when you carry your iBook into an AirPort-enabled area (and you have a password or permission to join that network), you gain wireless access to network servers and printers — which may require additional drivers and more login permissions. You also typically have access to the Internet via this network. But when you walk out of range, you leave the network behind, and your PowerBook becomes isolated. With Bluetooth, no fixed networks are needed — anywhere. Connections are temporary and spontaneous, and any and all devices can be mobile. Whenever Bluetooth-enabled devices come within range, they can discover each other, make a connection, and exchange information.

How It Works

Though Apple’s current beta Bluetooth driver supports only a few uses — Mac-to-Mac file transfer, synchronization with a Palm OS PDA, and Internet access over Bluetooth-enabled cell phones — the core Bluetooth protocols are in place. The specifics of how Bluetooth works are set as well.


Just like items on an AppleTalk network, Bluetooth devices constantly listen for an inquiry from other devices. When they receive one, they respond, announcing their presence. But this happens only when discoverability is enabled. Take the Sony Ericsson T68, a popular Bluetooth-enabled phone, for example. It’s not normally discoverable, so if you want to connect your Mac to the Internet via the phone, you have to wind your way through the phone’s menus to turn discoverability on. Only then can the Mac find it. Another type of device — say, a printer — might remain discoverable all the time.

When one device discovers another, the discovering device becomes the master and the discovered device becomes the slave. Clearly establishing these roles is important in keeping the two devices in sync (more on this later). They exchange their unique IDs and, if they have them, names.

Typically, the master then asks the slave to list the services it can provide. In the case of a phone, this might include the ability to initiate voice and data calls. For a multifunction printer, it might include faxing and printing services. Once the master knows what devices are available and what services they can provide, it can pass this information on to apps that may want to use them.


You need to decide when you want devices to be receptive to establishing a connection with other Bluetooth devices — connectability is a way to set that willingness. You may decide to turn your Mac’s connectability off if you don’t want anyone to bother you with file-transfer requests.

When two or more devices are connected, they constitute a piconet. A piconet can contain as many as eight active devices: one master and seven slaves. It can also contain more than 250 inactive devices. And a device can be a master in one piconet and a slave in one or more other piconets at the same time. Such overlapping piconets are referred to as scatternets.


In order to establish a trusted connection, two devices engage in a process known as pairing. For two devices to pair, they must first exchange a sequence of characters known as a passkey, and you often have to enter identical passkeys on both devices. Some devices — including your Mac under Apple’s Bluetooth software — have the ability to remember pairings, so the pairing process need not be repeated each time two devices reconnect. Pairing is required before an encrypted connection can be established.


To protect your data from unwelcome eyes while it’s being transmitted through the air, Bluetooth employs a 128-bit encryption method called Safer+. Though some people have raised concerns about the security of Bluetooth connections and wireless networks created on-the-fly, 128-bit encryption is considered adequate for the transmission of nonsensitive data. But for credit card transactions or restricted corporate or government information, it may not be enough.


Bluetooth radio transceivers operate in a range of frequencies between 2.4GHz and 2.4835GHz; the range is divided into 79 channels, each 1MHz wide. Every second, all the Bluetooth devices in a piconet change from one channel to another 1,600 times in synchronization, a process known as frequency hopping. The hopping sequence is calculated independently by each device in a piconet, but they all use the unique ID of the master as the basis for their calculations. This is what enables them to stay in sync.

The State of Things

Bluetooth on the Mac is in its infancy, much as USB was back in 1998, when Apple shipped the first iMac. As mentioned previously, all Bluetooth devices have a transceiver to communicate with others and transfer information back and forth. Unlike those first iMacs with USB, no Macs have transceivers built into them — you need to add one if you want to take advantage of the benefits Bluetooth has to offer.


Installing Bluetooth on your Mac is as easy as purchasing a $50 adapter manufactured for Apple by D-Link. It’s a tiny hunk of black plastic about the size of a piece of Bazooka bubble gum, with a USB plug on one end and a green LED on the other. It plugs into any available USB port. (At press time, Apple’s Web site said that this adapter was temporarily unavailable.)


The preview software bundled with the adapter (currently version 1.0p2) is also available for download from Apple and is equally easy to install. OS X 10.1.4 or later is required — Apple will not be adding Bluetooth support to OS 9.

The software adds a preferences pane to OS X’s System Preferences application. This is where the bulk of your interaction with Bluetooth takes place, for now. From here, you can configure preferences, such as whether your Mac is discoverable, whether it requires a passkey to establish a connection, or whether it uses encryption. This is also where you can search for and pair with other Bluetooth-enabled devices.

Included is an application called Bluetooth File Exchange — just drag a file onto its icon, and up pops a dialog box from which you can discover and select other Bluetooth-enabled Macs to send the file to. One very cool feature is that when the file arrives at its destination, the recipient’s Bluetooth software, if configured appropriately, automatically opens the required application, which displays the file. (Note that file transfer can be initiated only by the sender.)


Although some companies view Bluetooth as a low-cost wireless extension to IP networks (and some even sell stand-alone Bluetooth hubs), Apple is not among them. In Apple’s view, Bluetooth belongs in products such as mice, keyboards, PDAs, ink-jet printers, headsets, and digital cameras. And Bluetooth-enabled cell phones are a great way to establish fully wireless dial-up connections to the Internet. Wireless networking, however, is AirPort’s job.

It should come as no surprise that many of the Bluetooth products available today are phones and phone accessories — after all, Bluetooth originated at Ericsson, a cell-phone company. Bluetooth-enabled phones are just beginning to appear in the United States. But even though Apple’s preview software supports them, not many cellular service providers have upgraded their networks to allow cell-data services, known as third-generation wireless. Those that do offer cell data typically charge by the minute or kilobyte, and they offer the service only in limited parts of major metropolitan areas. Phone accessories, such as wireless headsets and hands-free car kits, will work with these phones but won’t yet work directly with the Mac.

Even the iPod is a candidate for a Bluetooth upgrade. Bluetooth headsets for use with Bluetooth-enabled phones are already on the market; with improvements in audio quality, they could conceivably be used with iPods as well.

Bluetooth products in many other categories are PC-only right now — such as HP’s $400 Bluetooth-enabled DeskJet 995c printer (888/999-4747,; 3Com’s $250 Bluetooth Printer Kit (800/638-3266,, for adapting printers so they support Bluetooth; and Bluetooth keyboards and mice — but expect all that to change.

The Last Word

Bluetooth’s potential is enormous. Given the interest in Bluetooth that Apple is attempting to generate among developers, it’s not unlikely that within a year or two, Macs will have built-in Bluetooth transceivers. And don’t be surprised if the next major release of OS X, due late this summer, includes Bluetooth connectivity software.

Early adopters can expect to struggle with using their Bluetooth phones to get online, and they’ll suffer through the arcane setup process for wirelessly synchronizing their Palms with their Macs. But just as Ethernet, AirPort, USB, and FireWire are taken for granted today, Bluetooth will be a natural part of the Mac’s future landscape. And the changes it will bring to the way we interact with computers may well turn out to be as profound as the introduction of point-and-click, in 1984.

Bluetooth in the Palm of Your Hand

Of all the wonders Bluetooth has to offer, one of the few things that Apple’s Bluetooth technology preview lets you do is synchronize Palm OS devices with your Mac. If your PDA has a Secure Digital slot, you can get a taste of the future by synchronizing it with your Palm Desktop software and other conduit programs. However, the process is anything but plug-and-play. For starters, to take advantage of Bluetooth on the Mac, you’ll need the $50 D-Link DWB-120M Bluetooth USB Adapter, for sale only by Apple (at press time, it was temporarily unavailable). Add the $129 Palm Bluetooth Card (800/881-7256, in the Secure Digital slot of a Palm m125, m130, m500, m505, m515, or i705, and you’ve got all the hardware you need.

Set Up Your Palm

The Bluetooth Card comes with Mac software, but the installer itself isn’t OS X native. You can run the installer in Classic mode, which places all of the installable items for the Palm in a folder at the root of whatever drive has Classic installed on it, rather than in your Palm Desktop folder. Launch Palm Desktop, and select Install Files from the HotSync menu. Instead of adding files one at a time, select the files in the Finder and drag them onto the Install dialog box. Although you don’t need to install every file — some work just with cell phones — there’s no indication of which are actually required to sync. Because they take up so little memory, however, you might as well install them all.

Synchronize and install your new software, and the Palm will display a dialog box with a Reset button. Click on Reset and let the Palm restart, and your Palm is ready for the Bluetooth Card. If you haven’t used this card slot before, know that it’s a push-push model — pushing a card in locks it, pushing it again releases a spring to remove it. Don’t pull, or the mechanism will be ruined. Remove the dummy card that comes with your Palm, and insert the Bluetooth card — once the card is recognized, your Palm will play a tone (if you have sound enabled).

Configure Your Mac

Then you’ll configure the Mac software. Under the Bluetooth System Preference’s Settings tab, make sure that the Discoverable and Require Authentication options are both selected.

Click on the Serial Ports tab. The Bluetooth-PDA-Sync option should be selected. If it isn’t, click on New and select the Use With A Palm Handheld option.

With this serial device created and enabled, you can select it in the HotSync Software Setup menu (HotSync: Setup, in the Palm Desktop application). Select the appropriate Bluetooth device from the list under the Connections tab.

Configure Your Palm

You must now instruct your Palm’s HotSync software to talk to your Mac. Select the HotSync icon; then either use the menu icon to select Connection Setup or simply write S.

Click on the New button and select PC from the Connect To Popup menu. In the Via menu, you should have Bluetooth as an option — select it. Then click on Tap To Find (under Device).

A Bluetooth Discovery dialog box will appear, showing its search for local machines. When it finds the Mac, the Palm displays the Discovery Results dialog box, which lists local devices. Select your Mac from the list. The Mac software will prompt for a passkey to secure the connection between the Palm and itself. Enter a short phrase or password.

The Palm likewise now prompts you with the Bluetooth Security dialog box. Enter the identical passkey, and select Add To Trusted Device List — the two are now paired, and you will not have to enter passwords for them again.

The synchronization should begin. If it doesn’t, try deselecting and selecting the Connection options in HotSync Software Setup and enabling and disabling HotSync.

If you normally use a USB cradle, your HotSync speeds will be slightly slower using Bluetooth, but you’ll notice a speed improvement over the older serial cradles. Either way, once you get it working, you’ll never sync the same again — Glenn Fleishman.