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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
You said it yourself - cable. If you both have ethernet you can just use a single swapped cable. Lo tech = cheap, quick easy reliable etc. etc.
Sorry, nothing profound to put here! (http://www.abacus4.com/
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.
I don't recommend you use the infrared ports for any serious communications. While it may be convenient for trivial tasks, I wouldn't commit anything as important as a file transfer to it. The link just isn't hardy. Do yourself a favor, get a crossover ethernet cable and just hook the two machines together.
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
Wireless (802.11b)...this is a great alternative...my LUG uses it all of the time, it's great because you get real high speeds out of it (over 10 Mb vs. 256k MAX for IR) and it's available almost everywhere...you'ld be supprised how much wireless is in the air.
... don't read everything you hear ... you're already mobile ... but then again, IR is worse because there is NO built-in security (except maybe the line-of-sight/distance thing)!!!
... You get fast, easy connectivity, without the whole line-of-sight requirement and you get a great mobile network card that you'll find yourself using more and more as time goes on.
As for security
You can easily find PCMCIA wireless cards for under $50
Not to mention that you can get Wicked Distance from 802.11b!!! Yes, this is a special case, but 100 meters is certainly no problem.
While IR is nice and will certainly be used (in other devices) for a long time to come, 802.11b should be your choice for mobile networking. It's worth noting that many companies are already including built-in 802.11b in their notebooks (either standard or as an option).
I just got a laptop a few months ago. I don't remember seeing a single one WITHOUT ethernet in my shopping.
;-)
I hope you're right. A former coworker of mine bought a Compaq about nine months ago-- don't know the model number-- that came without Ethernet. I hope the various PC laptop makers have come to the realization by now that Ethernet is important enough to build in.
Why would they be using the 169.254 subnet? I thought it would be 192.168 or 172.mumblemumble or 10.x.x.x subnets?
If you set your computer to get its IP info from DHCP, and no DHCP server is available, the computer will fall back to a self-assigned IP address. To self-assign, the machine picks a random address in 169.254, sends out a broadcast packet-- ARP, I think-- to see if anybody else on the local segment is using that address, repeats if necessary, and finally assigns the address to itself. All self-assigned addresses are in the 169.254.0.0/16 network. This is covered by an RFC, but I'm too lazy to look up which one.
This is also, incidentally, one of the foundations of Rendezvous. Rendezvous (a.k.a. ZeroConf) adds something called the multicast DNS resolver, which allows computers with self-assigned link-local addresses to refer to each other by name. Computer A sends out a multicast DNS packet asking for the IP address of the computer named "foo.local." Computer B is named "foo.local," so it responds with its own self-assigned IP. Computer A now knows what Computer B's IP address is, so they can communicate.
Until all the world is Rendezvous, you'll need to ask your friend what his IP address is before you can FTP (or whatever) to his machine. But you don't have to worry about assigning IPs to your machines or anything silly like that.
to show how 733+ this guy and his buddy are
Um... no offense, but do you maybe mean "1337"?
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.
One of the few problems I still have with using Linux as my sole platform for work is IR. I frequently find myself at some client site with a couple of colleagues with a need to move some files around. We all have Thinkpads with IR, and when we were all running Windows it was easy to beam stuff around. But with Linux, I can no longer participate effectively.
Yeah, I know about ircp, but it's quirky, unreliable and *dog* slow (less than dialup speeds) when transferring to a Win2K box. I've read that there's another approach that requires reconfiguring the Win2K side, but that's not really an option, because, usually, if the need is sufficiently urgent that it's worth doing there's no time to futz with things. It has to just work.
OTOH, I can't complain too much, since I didn't pay anything for ircp and I don't care enough to fix it myself, but it sure would be nice if someone else would do it (or if someone would post a reply saying they've done it, or that there's some better tool to use? Please? ;-)
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
Um... no offense, but do you maybe mean "1337"? ;-)
Just goes to show I'm not 1337 enough.
If you set your computer to get its IP info from DHCP, and no DHCP server is available, the computer will fall back to a self-assigned IP address.
Is this part of the RFC, or is it something that the implementers of various dhcp programs implemented? On a few linux boxes I have that get address via dhcp, they don't go for one of those addresses.
I hope the various PC laptop makers have come to the realization by now that Ethernet is important enough to build in.
My mother bought a Jetta last year. Ethernet port. I got one this year, Ethernet port. I looked at several others, all Ethernet ports. Now the really interesting thing is that I was looking at a few laptops the other day, and see that some of them are coming with 802.11b built in, like the TiBooks. The one that caught my eye was an IBM. One thing I noticed is that the smaller manufacturers were more likely to compete on features, whereas the big names competed on... their names.
I'm happy with my choice, but would have been just as happy with an iBook or TiBook (the former with the a smaller screen, the latter much more expensive.)
Jesus was all right but his disciples were thick and ordinary. -John Lennon
the original poster specifically said he didnt want to connect them via networking
No, the submitter said he didn't want to have to "build a small network," and that he wanted alternatives "other than cables." Using AirPort and self-assigned IP addresses, you don't have to "build a small network." For that matter, you don't have to "build a small network" if you use a crossover cable, unless you count plugging the cable in.
I stand by my original choice.
You can stand by whatever you like. I've already explained why you're wrong. Just to drive the point home: making two laptops-- one Mac, one Windows-- interoperate in the way you describe, with Bluetooth, is even more difficult than using IR between them. AirPort, on the other hand, is specifically designed to do what the submitter wants to do. Exchanging files over Bluetooth-- with what, XModem?-- is like carving roast beef with a screwdriver.
I'm done with you. If you want the last word here, be my guest.
I write in my journal
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.