WANs are wide area networks, like the internet, and LANs are, local area networks, like the wifi in your house.  PANs, personal area networks, are – i thought – a joke.  Presumably each Borg has a PAN so his headset, pda, cell phone, and ankle bracelet can talk to each other and when he sits down in his car the engine, radio, gps all join in.

So imagine my surprise when this weekend I found I was creating a PAN using Bluetooth.  Bluetooth is a standard full of promise which seems to specialize in delivering a frustration.  Two things lead to that frustration.  First there is lots of bad hardware.  Chips that don’t work very well, headsets that sound awful for example or software stacks that are buggy.  Second the standard has volumes of optional bits and peices; so usually it turns out the two devices you want to talk to each other don’t happen to support the necessary bits.  Sometimes that’s intentional, for example you can’t use your phone as a handset to talk to your computer since that would let your route around the cell phone company using voice IP.  The structure of the Bluetooth standards with all those optional bits and peices is typical of telco standards.

The fun I had this weekend was discovering that this phone I got and some of my Macs support Bluetooth PAN, one of those optional bits.  Using this it was trivial to let my Mac talk connect to the internet connection that the phone provides.  One, two, three: Do the usual bluetooth pairing, select connect to network from the bluetooth menu, oh … there is no step three.

In theory Bluetooth PAN supports multiple devices sharing the internet connection, but apparently my phone doesn’t do that.

This worked trivially on a MacBook Pro running Leopard.  But sadly it does not work on the MacBook Air – which in a typical Bluetooth user experiance – pretends to support Bluetooth PAN but it is unusable slow.  So for that machine I’m forced to switch back to more traditional Bluetooth DUN (dialup networking – a simulation of the dialup modems of my childhood).

I got into all this because I’ve been wanting to try AT&T’s $20 a month “unlimited” prepaid internet.  Right now you can buy a Z750a for $60 from their prepaid store – and if you poke around you can find online sites that will send you a rebate (after 90 days) of $25 or $30.  If you pop in $100 then the phone is good for year (buy from CallingMart with a coupon). I don’t intend to make any phone calls so that’s five months of internet access.    The Z750a supports Bluetooth PAN, DUN, and it can be a remote control for you Mac (I recommend declining all the options you don’t need).  If you buy the USB cable it is faster (800/300kpbs down/up) but the G3 HSDPA over bluetooth is pretty nice (400/30) as it is.  The USB cable appears to charge the phone as well.

This seems like a great solution for getting pretty good broadband into the home at a reasonable price.  A mac can share a connection to WIFI for example.

If you find your reduced to using BT DUN rather than PAN then you need to setup the modem’s dialing setup … I used this setup: dial: *99***1#, Username: WAP@CINGULARGPRS.COM, Password: CINGULAR1, APN: <leave this blank!>, CID: 1.  It picked the right modem dialing script automaticlly.

I’m enjoying having broadband pretty much everywhere I go.  The phone just sits in my bag.  ATT isn’t everywhere (click on data).