Today, you likely often authenticate or pay for things with a tap, either using a chip in your card, or with your phone, or maybe even with your watch or a Yubikey. Now, imagine doing all these things way back in 1998 with a single wearable device that you could shower or swim with. Sound crazy?
These types of transactions and authentications were more than possible then. In fact, the Java ring and its iButton brethren were poised to take over all kinds of informational handshakes, from unlocking doors and computers to paying for things, sharing medical records, making coffee according to preference, and much more. So, what happened?
Just Press the Blue Dot
Perhaps the most late-nineties piece of tech jewelry ever produced, the Java Ring is a wearable computer. It contains a tiny microprocessor with a million transistors that has a built-in Java Virtual Machine (JVM), non-volatile storage, and an serial interface for data transfer.
While it might be the coolest piece in the catalog, the Java ring was just one of many ways to get your iButton. But wait, what is this iButton I keep talking about?
In 1989, Dallas Semiconductor created a storage device that resembles a coin cell battery and uses the 1-Wire communication protocol. The top of the iButton is the positive contact, and the casing acts as ground. These things are still around, and have many applications from holding bus fare in Istanbul to the immunization records of Canadian cows.
For $15 in 1998 money, you could get a Blue Dot receptor to go with it for sexy hardware two-factor authentication into your computer via serial or parallel port. Using an iButton was as easy as pressing the ring (or what have you) up against the Blue Dot.
Indestructible Inside and Out, Except for When You Need It
Made of of stainless steel and waterproof grommets, this thing is built to be indestructible. The batteries were rated for a ten-year life, and the ring itself for one million hot contacts with Blue Dot receptors.
This thing has several types of encryption going for it, including 1024-bit RSA public-key encryption, which acts like a PGP key. There’s a random number generator and a real-time clock to disallow backdating transactions. And the processor is driven by an unstabilized ring oscillator, so it constantly varies its clock speed between 10 and 20 MHz. This way, the speed can’t be detected externally.
But probably the coolest part is that the embedded RAM is tamper-proof. If tampered with, the RAM undergoes a process called rapid zeroization that erases everything. Of course, while Java Rings and other iButton devices maybe be internally and externally tamper-proof, they can be lost or stolen quite easily. This is part of why the iButton came in many form factors, from key chains and necklaces to rings and watch add-ons. You can see some in the brochure below that came with the ring:
The Part You’ve Been Waiting For
I seriously doubt I can get into this thing without totally destroying it, so these exploded views will have to do. Note the ESD suppressor.
So, What Happened?
I surmise that the demise of the Java Ring and other iButton devices has to do with barriers to entry for businesses — even though receptors may have been $15 each, it simply cost too much to adopt the technology. And although it was stylish to Java all the things at the time, well, you can see how that turned out.
If you want a Java Ring, they’re on ebay. If you want a modern version of the Java Ring, just dissolve a credit card and put the goodies in resin.
Dallas TouchMemory ? we had a customer in ’96 (in Argentina) that use the Dallas versions DS1994 for access to a lab where vaccines were produced. It was used in a high humidity environment, the people of Dallas didn’t like high humidity :). It worked well, if I remember correctly.
I’m pretty sure that the UK pub giant Marston’s used these for quite a while. The staff had something which looked like this on a lanyard, and authenticated to the POS system with it
I’ve seen these in a lot of pubs. Of course, I don’t know if they’re actually Java Rings or just some other kind of token in the same form factor.
It’s interesting to look back at the old JVM, which was very much designed for embedded use — like, the only part of the language which allocated memory was the
newkeyword, and by restricting it to static initialisers only you ended up with a remarkably usable language which didn’t have any form of dynamic memory allocation, and because it was interpreted programs were very dense. And as it was a strict subset of desktop Java, development was trivial.Why is it bigger than Dallas challange-response button?
Nothing happened. That iButton became part of technology’s past. The rest of the buttons are still around, mostly. But the original idea lies with a timer built by BULOVA for the Explorer 1 sat. It became a watch. From there the Dallas people created them. I still use the RTC buttons for the stuff I build.
I desperately wanted some of these back in the early 2000’s, but they were export restricted due to the crypto, and could not be shipped to South Africa. They should be the same size as any other still-available iButtons, I would expect, if they are intended to use the same readers.
And yes, they are still in use here in South Africa for things like security guard patrol tracking – they have a smart baton that they touch to a series of iButtons (typically only holding a 64-bit identity) scattered around the site, that records the time that each identity iButton was touched to confirm that the guard was not sleeping on the job.