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Mac OS 8.6 introduced truly wireless data transmission  
Saturday, January 1, 2000 | by
Mac OS 8.6 introduced truly wireless data transmission through the enabling of communication between IrDa-capable Powerbooks and Ericsson and Nokia digital mobile phones. With the appropriate phone, it's now possible to send data from the computer through the infrared port to the phone and onto a receiving modem at your newspaper or ISP, potentially eliminating the need to purchase a PC Card and cable to do the same thing. I've been evaluating the effectiveness of OS 8.6's beefed-up infrared support for digital mobile phones for several weeks now, and am happy to report that this is a viable method, providing reliability and ease of use that meets or exceeds what you can expect using a top notch PC Card and cable tethered to the phone. There are quirks, however, and this transmission method is only compatible with certain networks. If you understand the quirks and have access to a compatible network, I highly recommend you consider this option for moving pictures when using a landline isn't an option.

A word on networks: For now, widespread digital data transmission is possible in North America and the rest of the world over GSM networks only. This isn't an issue in Europe and Asia, where the dominant digital mobile phone network protocol is GSM; in North America, the rollout of digital has been slowed and made unnecessarily complicated by the adoption of three separate protocols: GSM, CDMA and TDMA. Most, perhaps even all, GSM carriers offer digital data transmission, whereas only a small (but growing) number of CDMA networks, and no TDMA networks, do. And only GSM-compatible phones offer IrDa support at the moment. As a result, digital photographers in Canada and the United States that wish to take advantage of OS 8.6's infrared capabilities must choose a phone carrier that has deployed a GSM network (though this may change in the month's ahead). North American GSM carriers include:

United States GSM network coverage is very good, with about 3500 cities and 3 million customers with GSM service (called either GSM 1900 or PCS 1900 in North America). Notable holes in GSM network deployment in the U.S. include Chicago, Dallas and Washington, DC (Sprint Spectrum is shutting down its Washington GSM network in the fall, to be replaced by an Omnipoint GSM network sometime later). In most major metropolitan areas, however, expect to find a data-capable GSM carrier. In Canada, Microcell's Fido service is available in a handful of major cities. Outside the Americas, GSM networks are pervasive with multiple carriers in most markets to choose from. Search for a U.S-based GSM carrier in your area here.

Selecting a phone: Once you've selected a GSM carrier you'll need to select a phone with an infrared port, IrDa support, and built-in data capabilities. Lots of phones have infrared ports; relatively few include IrDa and data support. I've done all testing with an Ericsson CF 888, on loan from Mike Curliss of Ericsson Canada (thanks Mike). The Ericsson CF 888 is a dual mode GSM 1900 digital/AMPS analog phone, which means it will operate in voice mode on both North American GSM digital networks and North American analog cellular networks, and in data mode over GSM digital only. It includes an IrDa-compliant port on the phone's right side, and what Ericsson describes as an "in-built modem," really circuitry that will move data digitally through the air to the carrier. At the carrier the digital signal is converted to analog and passed on to the modem at the receiving end of the call the computer initiated to get all this magic underway in the first place. Compatible phones should include:

Plus the CF 888 I tested of course.

Positioning the phone: The phone must be placed so that its infrared port has an uninterrupted line-of-sight path to the infrared port on the Powerbook. The infrared port on my Powerbook G3/266 is tucked into the back corner and angled slight downwards. The Ericsson CF 888's infrared port is on its right side. Therefore, I've chosen to position the phone/Mac combo as shown in the picture at right. I've had no trouble establishing communication between the phone and computer when their infrared ports were on approximately the same horizonal plane as shown (though I usually prop up the rear of my Powerbook about an inch to aid heat dissipation, elevating the infrared port too).
[Image]

Moving the phone to the left, moving the phone to the right, even moving the phone about 3 feet from the back of my computer seems to cause no interruption in infrared communication. Nor does it seem to cause a drop in data throughput. Lifting the phone up off the desk, however, particularly when the phone is quite close to the Powerbook, causes an almost immediate warning message that the infrared connection is about to be lost. I've found the phone will work properly 100% of the time if I place it about 8 inches back from the Powerbook's infrared port, being careful not to elevate the phone much higher than the Powerbook itself.

Configuring the phone: The Ericsson CF 888 is configured by choosing Activate IR port from its menu of options. Unlike some other phones, the CF 888 doesn't seem to automatically deactivate the IR port after a period of inactivity. I prefer it this way. Configuring another phone may be different, but it shouldn't be complicated.

Configuring the Mac: If you have a late-model Powerbook with an IrDa-compliant infrared port and OS 8.6 installed, you should have all the computer you need. Compatible models include the Powerbook 3400, Powerbook G3, Powerbook G3 Series (WallStreet) and Powerbook G3 Bronze (Lombard). OS 8.6 essentially treats the infrared port like an additional (or only, in the case of the newest Powerbooks) serial port on the rear of the Powerbook. Once the Mac is configured, a selection called Infrared Port will appear in almost any Mac telecom application.

To configure the Mac for infrared:

  1. Choose Control Panels > Infrared from the Apple menu. The Infrared control panel will open.
  2. Click Options.
  3. Select the IrDa radio button, then ensure that "Notify me if the Infrared connection is interrupted" is checked on.
  4. Close the Infrared control panel.

That's all that's required to ensure that infrared capabilities in OS 8.6 are configured correctly. If you intend to use Apple's own OT/PPP Internet connection software or Apple Remote Access, you must also change a setting or two in the Modem control panel.

To configure the Modem control panel:

  1. Choose Control Panels > Modem from the Apple menu. The Modem control panel will open.
  2. Choose Configurations from the File menu. The Configurations window will open.
  3. Select a configuration in the list and click Duplicate.
  4. Enter a name for the configuration, ie "Ericsson Data," then click OK.
  5. Click Make Active.
  6. Choose Infrared Port from the Connect via popup menu.
  7. Choose Ericsson Infrared or Nokia Infrared from the Modem popup menu. The choice you make is dependent on the phone you have of course.
  8. The other settings in the Modem control panel shouldn't affect the connection, but just to be sure you may wish to set the Sound to On, Dialing to Tone and check Ignore dial tone on.
  9. Close the Modem control panel and click Save when prompted.

If you've already configured the Remote Access control panel to dial your Internet Service Provider, chances are you won't have to change any settings within it. Note, however, that to access the data services at some carriers, especially when roaming, you may need to set up Remote Access to dial the area code and the phone number, even when dialing a local call. If you intend to make an Apple Remote Access connection to your newspaper's network, then you may have to change the setting in the AppleTalk control panel to Remote Only and ensure that AppleTalk is active.

All other telecom applications include their own interface for modem configuration. Configuring them for infrared communication via a GSM phone is no different than for a regular landline modem: choose a port, in this case the Infrared Port, enter a modem initialization string and port speed. For example, to configure the wonderful Zmodem file transfer application GlobalTransfer:

  1. Choose Modem Setup from the Setup menu. The Modem Setup menu will open.
  2. Choose Infrared Port from the Macintosh port popup menu.
  3. Choose Custom from the Manufacturer popup menu, then enter AT&F into the Modem init string field, and choose 115,200 from the Port speed popup menu. Click OK. The initialization string AT&F sets up the phone's built-in data capability to its default configuration, which will almost always be okay for data transfer regardless of the phone model. If it doesn't work, however, you might try the following (this is the initialization string stored inside both the Ericsson Infrared and Nokia Infrared modem scripts that ship with OS 8.6.):

AT&FE=0&C1S0=0 (0s are zeros)

Each telecom app's modem setup will be a variation on this same theme. See below for a list of applications that I successfully used with the Ericsson CF 888.

NOTE: Some networks require that the Port speed be set to 9600 or you will experience a stall in data throughput during file transfers, followed by disconnection eventually. I've experienced this over Omnipoint and Microcell networks, but not VoiceStream, Aerial or several European networks. This is not specific to GlobalTransfer; the problem may occur in any telecom application. I recommend that you always try the higher port speed first, as it will usually result in slightly faster JPEG file transfers, switching to 9600 only if you experience difficulties.

Making a connection: Once you've configured the phone, positioned it properly and configured the Mac, click Connect, Start, Login, Ignite or whatever the button is called in your telecom application to get things underway. Most phones will indicate the number being dialed on their display, and that their attempting to connect through the carrier's data service. If the phone or software displays a message that no carrier was detected, try adding the area code of the destination modem you're dialing into the dialing string, as that error message may indicate that the call isn't being routed through the data service properly. If you connect successfully, then accidentally knock the phone off the desk, you will probably see this dialog:

[Image]

Normally, re-positioning the phone will clear the dialog and resume the file transfer. Disconnecting in the telecom app will terminate the connection and hang up the phone, so there should be no need to hang up manually.

Supported applications: Based on my testing, I'm confident that most if not all telecom applications that work in OS 8.6 with regular modems will work with infrared. I successfully connected (and transfered files where applicable) with the following applications:

NOTE: I was not successful with Apple's OT/PPP connection software or Apple Remote Access, though the cause is probably something specific to my setup. Photographer Paul Willis in the UK indicates he's had no problem using nothing but OT/PPP to surf the net via his Ericsson SH 888 phone. FreePPP has worked, however, and is the connection software I prefer, so this incompatibility, at least on my Powerbook at this moment, isn't much of a concern.

Infrared quirks: This section describes some of the quirks I've experienced in the last several weeks of testing.

  • If the ambient light is very bright, establishing an infrared connection between the phone and computer is nearly impossible. Placing a small cloth or other light blocker over the phone/computer infrared connection to keep out extraneous light has solved the problem for me when transmitting outdoors.

  • In some, but not all, modem programs the CF 888 takes a couple of minutes to reset after hanging up a data call. This is annoying, but either waiting for the phone to reset, or manually deactivating and reactivating infrared support on the phone, is an easy workaround. Still, I'm curious as to why some telecom applications send the right kind of hangup command to the phone and others don't. ZTerm 1.01 and Telefinder Pro 2.2.3 in terminal emulation mode were the only ones to consistently hang up the phone properly, such that a new data call could be initiated immediately without fussing with the phone's infrared settings.

  • If it isn't possible for you to position the computer and phone so that their infrared ports can see each other, as is sometimes the case when transmitting from a car, then one quirk of infrared connectivity is it may not be suitable for use 100% of the time. The alternative for Macs is a PC Card and cable that connects to the data accessory port on certain phones. Since this report is about infrared I'm not going to go into detail about PC Card options. I will say, however, that I've successfully transmitted hundreds of pictures with either a TDK Global Freedom 5660 or Psion Dacom Gold Card Global and a cable running to my Nokia 6190 GSM phone. Either of these PC Card and cable combos cost in excess of US$300 (though they also serve as top-notch landline modems) and the cables are somewhat easily broken, which is why I'm excited about infrared replacing both the cost and breakability issues associated with transmitting via PC Card. If you intend to transmit from your car a lot, however, you may consider it necessary to go the PC Card route instead of, or in addition to, infrared.

Other wireless thoughts: Currently, data transmission over a GSM digital phone, while reliable, is slow. Expect throughput of about 1K/second, or about a 1/3 of the speed of a solid landline connection. Both handset and networking equipment is gradually speeding up,however, with the future for wireless data transmission from digital phones looking bright. Some GSM networks will be upgraded to 1.5K/second throughput this year; Omnipoint's network conversion is already underway. Other GSM carriers are planning to skip this step and go right to GPRS, a GSM data transmission technology that will support real world throughput of between 10-15K/second. While this is at least a year away for most, Finnish carrier Sonera has already announced availability of GPRS on their network.

Meanwhile, CDMA carriers are gradually beginning to offer digital data transmission with throughputs between 1 and 1.5K/second. While it will take some time before most small to mid-size CDMA carriers offer data services, Sprint PCS, the United States' largest CDMA carrier with nationwide service, is expected to offer digital data transmission before the fall. To move pictures over CDMA, at the moment the options appear to be restricted to a small selection of Qualcomm phones and the company's Data Connectivity Kit, which is a cable that runs from the phone to the serial port on a PC (or Mac with an inexpensive cable adapter, plus a serial port adapter for Macs with USB ports in place of serial ports). In the next several months, however, infrared and other options for CDMA digital data transmission will begin to appear from Nokia, Motorola and probably other vendors as well.

Eventually, if the various wireless standards bodies can get it right, the so-called 3G (third generation) wireless mobile phone standard will blend several incompatible protocols into (I hope) just one with some minor internal variations. After a year of rancour, it appears that things are finally settling down, and that a standard that everyone agrees to will be settled on by year's end. That will pave the way for some way-cool wireless data functionality in the next millenium, including file transfer throughput of between 30K and 200K/second. It's expected that the conversion costs for 3G networks will be huge, so it's by no means certain that all or even the majority of carriers will adopt 3G for some time. In other words, don't break out the champagne just yet. Do get excited about the fact that digital wireless data transmission is already making the life of the digital photographer easier, and that the future network improvements will eventually leave traditional landline analog data transmission in the dust. And if you're still trying to transmit your pictures over an analog cellular carrier, punt your analog service and sign up with a GSM or CDMA carrier instead.

Also, temper your enthusiam for any mobile phone technology with some caution when using it extensively for voice communication. Some new European research is suggesting a link between mobile phone use and short term memory loss, headaches and increased incidence of brain tumours on the side of the head the phone is used on. While there has been anecdotal evidence to suggest a link for several years, much of it has been dismissed as quackery. This latest work, however, appears to be the first study that with some solid scientific grounding to it. The scientists who conducted the study are careful to point out that their work does not definitively indicate that there is a link, but rather that there is enough evidence to warrant an expanded examination of the health risks from continual exposure to the low levels of thermal radiation emitted around the antenna of mobile phones. Representatives from the big three mobile phone makers, Motorola, Nokia and Ericsson, have reacted by saying that there is no concrete scientific evidence. Given the possibility of serious health problems resulting from long term and perhaps extensive use of mobile phones, it seems like a good idea to limit the amount of time one talks on the phone with it pressed against the ear. Using a headset or hands-free unit whenever possible is my solution until more is known about this potentially serious problem. For a look at some products designed to shield the user from mobile phone radiation, check out the Mobile Phone Safety Centre.

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