WebHashcash
Beta

Introduction

Installation

Compatible Browsers

Sites That Use It

Web Browser Compatibility

WebHashcash is compatible with every modern web browser that supports Java and JavaScript.

If the user's browser also supports LiveConnect, stamp generation will happen completely transparently. Otherwise, the user will be required to enter a simple string of about four characters to apply the stamp which was generated by the applet.

Browser Compatibility Table

Windows 2000/XP1 Mac OS X Linux
Mozilla Full Manual Full
Firefox Full Manual Full
Netscape Full Manual Full
Camino N/A Manual N/A
Internet
Explorer		 Full Manual N/A
Safari N/A Full N/A
Konqueror Unknown Unknown Full
Opera Full Manual Unknown
OmniWeb N/A Full N/A

Legend
Full: WebHashcash operates completely transparently.
Manual: WebHashcash operates correctly, but requires that the user enter a string of about four characters in order to apply the stamp.
None: WebHashcash does not work on this browser.
Unknown: WebHashcash has not been tested on this web browser.
N/A: This web browser does not exist for this platform.

(Latest browser versions assumed.)

1. Java is not installed on all copies of Windows 2000/XP. This table assumes a Java installation.

Why does WebHashcash use JavaScript and Java, rather than just JavaScript?

Scripting languages such as JavaScript are interpreted on the fly, and therefore run very slowly. They are tailored towards basic web content manipulation, not high-powered CPU calculations. By contrast, Java is compiled once, and runs relatively quickly. JavaScript code would require around 100 times the amount of CPU time to generate valid Hashcash stamps.

WebHashcash by David Schneider-Joseph. I invite all feedback.
Based on Hashcash by Adam Back.