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Except that any secure digital cash system must have the property that I mentioned -- the tokens must grow with the number of transactions:

ftp://www.hacktic.nl/pub/mirrors/Advances%20in%20Cryptology/HTML/PDF/E92/390.PDF

I'm not sure if "token" is a valid concept in bitcoin. There are just practically unlimited number of "accounts" which each hold a variable amount of bitcoins. Also, there is a central authority of sorts for bitcoin, which is the public blockchain that stores all the transactions in bitcoin network, and makes it possible to know the value of every account. That transaction record is managed in a peer to peer fashion.

So tokens don't grow since there are no tokens to begin with.

Except that any secure digital cash system must have the property that I mentioned -- the tokens must grow with the number of transactions:

ftp://www.hacktic.nl/pub/mirrors/Advances%20in%20Cryptology/HTML/PDF/E92/390.PDF

Hmm, not entirely accurate I believe..

This (ad at the bottom of the page) is where XS4ALL started. They were basicly the first public ISP in the Netherlands (tho I am not entirely sure, 'stichting Simplex' was there at around the same time from what I recall)

Demon and XS4ALL definitely have things in common, but I think that has more to do with both having started in the very early days of public internet access, and still believing that they connect computers to a big network (as opposed to the content focus that many an ISP seems to have). Both give you a fixed IP and your own hostname, allow you to run servers including smtp and http etc.

At any rate, XS4ALL grew out of a desire to provide cheap access to the 'live internet' as opposed to the then common uucp mail/news access. The people behind it had been involved in the Datanet 1 (X25 network similar to Tymnet and the like) and the BBS scene, and had been running a somewhat substantial (100+ nodes) uucp network for some time. They went for nothing less making it possible for every person with the proper equipment to become a full host on the Internet, an attitude which is still pretty much there in modern XS4ALL.

AH well.. thanks for reminding me of that time.. had fun looking up some info on it today, and reading back about the early days of Internet access overhere. Heh, to think that I have a nice 8mbit up/1 mbit down connection here that costs about 1/5th per month when compared to the initial internet connection (at a whopping 19k2) that XS4ALL used themselves to get on the net :)

I did not use XS4ALL much during those early days, mostly because I got a free account from IGN with which I had internet access with local dialin from about any major city worldwide, and I had a rather good access deal with Simplex for my home network. I can confirm your comments about the quality of XS4ALL and their generally nice attitude towards issues that concern their private customers.

Gongrijp knows what he's talking about. He was one of the founders of Hacktic magazine, a "magazine for techno-anarchists" that was published from 1989 till 1994. Hacktic publications included schematics for pay television descramblers, detailed expositions of operating system vulnerabilities, articles on "social engineering" (I think they might even have coined the phrase), and numerous topics on hacking the phone company ("phreaking") and war dialing.

These guys have also organized some huge hacker conferences such as Hacking at the End of the Universe in 1993 and Hacking In Progress in 1997 (I was there in '97). Later Hacktic professionalized and they became the first ISP in the Netherlands. Still later that turned into XS4ALL, probably the best ISP in the Netherlands.

Through everything, Gongrijp ("Public Enemy #1") was a driving force. If he says the phone is secure, then that's a pretty damn strong endorsement.

These guys have been on the forefront of allmost any ethical debate concerning the Internet and digital freedoms in general. XS4ALL was formed in 1993 by the infamous hackergroup Hacktic(RIP) and was the first dutch ISP to allow access to private persons. Since then they haven't like so many others sold out to profitmaking instincts but kept to their goal of providing high quality, afforable internet access to the masses. Over the years they've suceeded without giving in on netpolitical views like the right to privacy, freedom of speech and freedom of choice.

- On numerous other occasions they've been in court defending the privacy of their costumers and other basic rights.
- Threre's no single ad on any of their pages. They're an internet provider, not a advertising agency! Me and many others will gladly pay some more 's for that.
- They offer analog, isdn(128k), gsm, gprs and adsl access and their service includes free licences for mcafee virusscan and pgp software (all platforms). Do you know any other ISP that does that?
- There's a whole lot of other goodies you don't find at your average ISP: a telnet/ssh shell, static ip with bSMTP (if you want it), adfree secure webmail, and good public irc, gaming and hosting servers.
- Their bussiness services are also quite exelent.
- And they're definitly the only isp in the world that grows marijuana in the workplace!!! (in dutch).

[DISCL: No, I don't own stock or work there, I'm just a ver loyal costumer that has been with them since 1996 both privatly and professionaly.]

SqyD

I've had a shell account with xs4all from the very beginning when the name was hacktic. In 1998 they sold out to the evil local telecom giant KPN. Almost three years later it's still a quality ISP and if I need to get hold of a techie or even the CTO I can usually find them on IRC. If not, I can email them and they'll respond fairly quickly.

Hack-Tic (a dutch hacker magazine) published in 1992 an article about eavesdropping on telephones that are on-hook (unfortunately the article is written in dutch, but you're probably more interested in the schematics at the end of the article anyway).

I believe the technical term is high-frequency flooding, but IANAEE[0].

The phones on which the technique worked were in fact the older models that do use an actual physical switch. The vulnerable phones used a switch that contained several metal strips.

Basically it works like this: instead of a direct current the phone is fed a high-frequency alternating current. Because of the high frequency the contacts of the switch will act like a capacitor, allowing a current to run through the circuit. The microphone does work that way!
I have seen it work and I was impressed. Audioquality wasn't quite good, but the demonstration did something supposedly impossible so hi-fi audio wasn't important, the conversation in the room was intelligible.

(quite funny: the dutch telecom provider first denied it was possible, but soon started to sell kits to prevent eavesdropping using this technique)

On modern telephones this wouldn't work I guess, simply because the physical switch isn't the only thing inbetween the microphone and the phoneline (amplifiers, filters, whatever...).

I hope this helps...


[0] I am not an electrical engineer...

Hack-Tic (a dutch hacker magazine) published in 1992 an article about eavesdropping on telephones that are on-hook (unfortunately the article is written in dutch, but you're probably more interested in the schematics at the end of the article anyway).

I believe the technical term is high-frequency flooding, but IANAEE[0].

The phones on which the technique worked were in fact the older models that do use an actual physical switch. The vulnerable phones used a switch that contained several metal strips.

Basically it works like this: instead of a direct current the phone is fed a high-frequency alternating current. Because of the high frequency the contacts of the switch will act like a capacitor, allowing a current to run through the circuit. The microphone does work that way!
I have seen it work and I was impressed. Audioquality wasn't quite good, but the demonstration did something supposedly impossible so hi-fi audio wasn't important, the conversation in the room was intelligible.

(quite funny: the dutch telecom provider first denied it was possible, but soon started to sell kits to prevent eavesdropping using this technique)

On modern telephones this wouldn't work I guess, simply because the physical switch isn't the only thing inbetween the microphone and the phoneline (amplifiers, filters, whatever...).

I hope this helps...


[0] I am not an electrical engineer...