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Connecting PCs and Macs via Infrared Communications?
Stuee asks: "Isn't it about time my friend and I could sit opposite each other on the train and share documents or images without having to build a small network?! I mean, what's the point of both systems having infrared, and software to bridge the platform gap, if we can't connect? It's so frustrating that my XP laptop reports that my friend's iBook is in range, but cannot do anything about it, especially when my phone (which was a fraction of the cost of either laptop) and pocket device can communicate with both machines without any problem! If anyone knows of a workaround for this (other than cables), I think there would be a lot of people interested in hearing about it.
Thanks for listening."
No, no, no. Bluetooth is not a computer-to-computer network technology. Bluetooth devices have to be paired before they can be used together, and once paired, they can be used at any time without authentication. Think of Bluetooth as a computer-to-peripheral technology. Anyplace you'd use a serial cable, or a USB cable, or a parallel cable, you can-- at least in principle-- use Bluetooth.
What this guy really needs is good old AirPort wireless networking. He said his friend has an iBook; any iBook can take an Apple AirPort card (MSRP $99), and they're take about three minutes to install. PCMCIA cards for PC laptops are also available, but I haven't a clue what they cost. Setting up a computer-to-computer network is the easiest thing in Mac OS 9 or OS X. Once established, the Windows machine should be able to sign on, but you never know for sure with those wacky third-party AirPort cards.
Of course, if the laptops in question were capable of this, he probably wouldn't be asking the question. The AirPort answer is just too obvious.
Furthermore, since he's talking about one Mac laptop and one PC laptop, chances are fair that Ethernet isn't an option. (All reasonably modern Mac laptops have Ethernet, but even today a lot of PC laptops don't. Which amazes me, but that's another conversation.)
To Stuee: If both computers do, by luck, have Ethernet, just carry a crossover cable with you. It's easy and lightweight. And you don't have to "build a small network" to use it, unless you count plugging the cable in as building a small network. At most, you'll have to ask the other guy for his IP address-- if you're using FTP or some such. It'll be in the 169.254 subnet. You are using self-assigned IP addressing on these little trips, right? It makes life easy.
And if the Mac laptop is reasonably recent, you don't even need a crossover cable. I forget exactly when it happened, but recent Apple laptops have auto-sensing MDX ports on them, which means you can go computer-to-hub or computer-to-computer with a regular Ethernet cable.
I know the you said you were looking for workarounds "other than cables," but if you can't use AirPort, an Ethernet cable is the way to go.
I write in my journal
The only trick is that you need to choose IR (or in some cases it says Virtual IR) as the COM port instead of choosing a modem or COM port. Oh yeah, and make sure the two IR ports recognize each other.
The iBook HAS NO IR PORT.
If voting were effective, it would be illegal by now.
I presume this isn't a recent iBook, since all of the new ones, at least here in AU, have no IR port. Just wondering... do us Australians get a raw deal?
No... you're absolutely right. That brings up a great point. There's never been an IR port an any iBook. Maybe the submitter meant PowerBook instead; many PowerBooks, including the G4, have IR ports on them. (Although I'm not sure why.)
To a non-Mac person, the distinction between an iBook and a PowerBook might not be immediately obvious. Benefit of the doubt applies here, I think.
I write in my journal
PPP is the protocol you'll probably need to use, but you have a couple of problems.
6 617
k /infrar ed/WinXP-IrDa.asp
The easy one: One of you will have to act as a PPP server.
Harder:
Mac OSX 10.1 doesn't support the IR ports on some powerbooks. http://docs.info.apple.com/article.html?artnum=10
MS has added some layers that complicate basic IRDA behavior, and implemented their own IrNET network protocol instead of the IrLAN standard. I'm not even sure you can get raw access to the IRCOMM layer that allows you to treat an IR port as an ordinary serial port.
http://www.microsoft.com/hwdev/tech/networ
http://www.irda.org/
The real difficulties of "building a small network" are difficulties of software, not hardware.
There is one advantage of stringing a crossover cable across the aisle. You could end up with both laptops flying towards the ankles of the person you trip.
Assembly is the reverse of disassembly.
Called a cross-over cable. Swap the green and orange pairs on one side to make one.
Perhaps you should download a demo of PC MacLAN and install that on the XP machine.
;) USB add-on maybe?
You should be able to bind Appletalk to the Infrared port on MacLAN.
From there, you assign infrared on the Mac (in OS 9 or X) to be the current Appletalk port, restart file sharing and away you go.
Seriously, though: go for the Airport/Orinoco 802.11 card option. It's one hell of a lot faster and more reliable. You're not gonna be able to do Unreal Tourney or Warcraft matches (very well) over IR because the speed is too low and the latency is too high. You've also got line-of-sight issues. Just try synching a palm over IR and you'll see what I mean. It's freaking SLOW.
I'm also curious how you got an iBook with an IR port.
TiBook, yes. iBook, no for built-in.