Thursday, March 26, 2009

Bluetooth teething problems

(It's a bit late in life to have teething issues, methinks.)
I had a bluetooth keyboard, but I stopped using it, because every time I woke up the computer, it was a hassle waiting for the machine to find the keyboard. And then recently, my Playstation 3, which I use to play blu-ray disks (because the dedicated player I have is a nightmare of slowness), stopped reacting to its remote control, which had to be purchased separately and is a blutooth device.

So I asked our friend Bert the engineer for advice and he said something about having said many years ago that blutooth was a bad idea. So I asked him:

"Do you think that the very idea of wireless control (bluetooth) is bad and can't be done well, or just that bluetooth itself is poorly developed?"

Over to Bert:

A bit of both, I suppose. The very idea of a self-configuring RF network (the base concept behind BT) involves so much wishful thinking that it borders stupidity. Don't get me wrong, it's feasible, but not in a world where quality products have become more a memory than an expectation. There are many problems with this concept, the worse being the lack of available bandwidth, simply not enough channels available for this idealized wireless concept.

There are also design issues. Take digital wireless phones, for instance (I do mean land line phones, not mobiles). They face the same basic problems, but they have two advantages that make a world of difference. Firstly, the handset(s) are recharged in the base that connects with the outside world. When you drop the handset in the base, there's a physical connection available between the two units and that's when registration takes place. No contact, no registration. Lost registration? Simply re-establish physical contact for a couple seconds. This makes it impossible for your neighbor's handset to accidentally (or maliciously) hop onto your network.

Secondly, digital phones and their corresponding bases are both programmed and debugged by the same group of people, so software issues are much more easily identified and fixed. BT was made vendor-independent from the start, though, and with no restrictions on the size or shape of the units. That's where you enter a world of pain. Makes it nearly impossible to specify a "mating ritual" involving physical (electrical) contact. And the software issue instantly evolves into a guaranteed nightmare by implying compatibility between thousands of devices from hundreds of vendors across dozens of application fields.

One may argue that this is no different than, say, USB devices, but I beg to differ. If you buy a crappy USB device, you are always free to pull the plug and throw away the device. Or you could compromise if, for example, you own two scanners that simply won't co-exist, all you have to do is make sure that both devices are never plugged in simultaneously. But how are you going to do that with RF devices? Especially that some of the problem devices may very well belong to your neighbor...

Performing on-the-fly, unconfirmed device registrations is stupid bordering suicidal, IMHO, but it's one of the fundamental goals behind Bluetooth. You walk into a BT-active space with your BT-enabled device and it magically and seamlessly integrates itself into the existing network. Yeah, right. I read about this idea in a magazine over 15 years ago (iirc) and it immediately seemed like a dumb idea, and I haven't found any reason to change my opinion since.

Take a PS3 in your average apartment tower, for example. All living rooms are located either one on top of the other, or mirrored with a simple wall between the two. So it may very well be that your neighbor's PS3 is the BT device physically closest to your own PS3. If he stores his remote near his unit, all bets are open. Especially if he read an article on power vampires and decided to unplug his PS3 when not in use. His remote loses registration when he unplugs his PS3, and thus goes on the hunt for a new station to register with: yours!

I could go on further, but I guess you get the picture by now. As if it was not enough that a BT link is susceptible to be killed at any time by interference from other RF sources (not even necessarily BT, since everybody shares the little available bandwidth), but all BT devices are also basically predators hunting for a socket to occupy, making odds of usurpation quite high as well.

Now, I don't really know how the problems are solved in the real world, because I just avoid BT altogether, but I suspect that many more-or-less inventive, yet not necessarily good or especially inter-operable schemes have been devised, creating endless confusion. Kludges built atop a wart, if you ask me.

Be well, Bert


I shouldn't wonder if other devices are actually the issue, I had not thought about that. I've noticed that in this apartment recently, I can sometimes see over half a dozen wireless networks! so it stands to reason that something similar may be happening with bluetooth (and it does have quite a range, I could easily use it through two walls, when the remote still worked).

8 comments:

Pascal [P-04referent] said...

"But how are you going to do that with RF devices? Especially that some of the problem devices may very well belong to your neighbor..."
Hire a trigger and off your neighbors. Simple!
Don't forget to specify that he must cut the house's power when he leaves. And dump all portable devices in the sink.

"Especially if he read an article on power vampires and decided to unplug his PS3 when not in use.
Now, I wonder who could have given him such a stupid idea?...

but all BT devices are also basically predators hunting for a socket to occupy, making odds of usurpation quite high as well."
Survival of the electronically strongest!
You were saying, about vampires? Watch out for the emerging of the first cyberwerewolves! "They come in packs, and hunt the data of your game saves. Now in theaters."

"I could easily use it through two walls, when the remote still worked"
What was wrong with good, old-fashioned infrared? How many people, anyway, use a remote control for a movie viewing apparatus when they're not within direct visual range???

Eolake Stobblehouse said...

I'm guessing they wanted to save the cost of an infrared port, since all the gamers don't buy the remote, but use the game comptroller.

Bert said...

What was wrong with good, old-fashioned infrared?

Requires line-of-sight, and that's no good for something like boxing (on the Wii, for example).

Also won't work for the TV in the bedroom (you'd be surprised how common that is).

Eolake Stobblehouse said...

Because for certain kinds of movies the sheet tent gets in the line-of-sight?

Bert said...

Because for certain kinds of movies the sheet tent gets in the line-of-sight?

No, I meant one player (usually in the living room) for all the TVs in the house.

The remote is not recommended for the other kind of movies, it tends to become tacky and eventually stops working because of the stuck keys. Is that what happened to yours?

Eolake Stobblehouse said...

No, I learned my lesson when young and wrap all mine in cellophane wrap.

Alex said...

Have you thought of an IR extender?

They make IR repeaters for people who have all there hi-fi/AV components in a closed (no glass) cabinet.

I would not be surprised to find a IR to X10 to IR system. I don't know if they use X10 in the UK, but it is used in the US. Basically your AC (power not HVAC) become a low bandwidth copper network.

I still find domestic AV distribution systems a bit weird. Having two or three satellite receivers feeding an RF mux to distribute to 8 TV's in the house. Our 1 TV in the house is more often then not sat there with a black screen taking up space, why do you need 8? Mind you I still think of TV as "We've got a 4th channel now".

Pascal [P-04referent] said...

OK, the Wii has an excuse.
TV, VCR and DVD remotes don't.

"Why make it simple when it's so simple to make it complicated?" - (Shadok proverb)