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78 >1. General Information</H1
86 >1.1. What is this new version of <SPAN
91 > In the beginning, there was the
93 HREF="http://www.junkbusters.com/ijb.html"
97 >Internet Junkbuster</SPAN
100 by Anonymous Coders and <A
101 HREF="http://www.junkbusters.com/"
105 >. It saved many users a lot of pain in the early days of
106 web advertising and user tracking.</P
108 > But the web, its protocols and standards, and with it, the techniques for
109 forcing users to consume ads, give up autonomy over their browsing, and
110 for spying on them, kept evolving. Unfortunately, the <SPAN
114 > did not. Version 2.0.2, published in 1998, was
115 (and is) the last official
117 HREF="http://www.junkbusters.com/ijbdist.html#release"
122 HREF="http://www.junkbusters.com"
124 >Junkbusters Corporation</A
126 Fortunately, it had been released under the GNU
128 HREF="http://www.gnu.org/licenses/gpl.html"
131 >, which allowed further
132 development by others.</P
134 > So Stefan Waldherr started maintaining an
136 HREF="http://www.waldherr.org/junkbuster/"
138 >improved version of the
140 >, to which eventually a number of people contributed patches.
141 It could already replace banners with a transparent image, and had a first
142 version of pop-up killing, but it was still very closely based on the
143 original, with all its limitations, such as the lack of HTTP/1.1 support,
144 flexible per-site configuration, or content modification. The last release
145 from this effort was version 2.0.2-10, published in 2000.</P
149 HREF="http://www.privoxy.org/user-manual/copyright.html#AUTHORS"
153 picked up the thread, and started turning the software inside out, upside down,
154 and then reassembled it, adding many
156 HREF="http://www.privoxy.org/user-manual/introduction.html#FEATURES"
162 > The result of this is <SPAN
166 stable release, 3.0, was released August, 2002.
179 >? Why a name change at all?</H3
191 >Privacy Enhancing Proxy</I
195 modification and junk suppression allow you to browse your
208 HREF="http://junkbusters.com/"
210 >Junkbusters Corporation</A
212 continues to offer their original version of the <SPAN
220 >-derived software under the same name
223 > There are also potential legal complications from the continued use of the
227 > name, which is a registered trademark of
229 HREF="http://junkbusters.com/"
231 >Junkbusters Corporation</A
233 There are, however, no objections from Junkbusters Corporation to the
237 > project itself, and they, in fact, still
238 share our ideals and goals.</P
240 > The developers also believed that there are so many changes from the original
241 code, that it was time to make a clean break from the past and make
242 a name in their own right, especially now with the pending
243 release of version 3.0.</P
268 > left off. All the old features remain.
272 > still blocks ads and banners,
273 still manages cookies, and still helps protect your privacy. But, these are
274 all enhanced, and many new features have been added, all in the same vein.
277 > The configuration has changed significantly as well. This is something that
278 users will notice right off the bat if upgrading from
292 > and much more has been
293 combined into the <SPAN
296 > files, with a completely different
298 HREF="../user-manual/upgradersnote.html"
307 >'s new features include:</P
314 > Integrated browser based configuration and control utility at <A
315 HREF="http://config.privoxy.org/"
317 >http://config.privoxy.org/</A
324 tracing of rule and filter effects. Remote toggling.
329 > Web page content filtering (removes banners based on size,
333 >, JavaScript and HTML annoyances, pop-up windows, etc.)
338 > Modularized configuration that allows for standard settings and
339 user settings to reside in separate files, so that installing updated
340 actions files won't overwrite individual user settings.
345 > HTTP/1.1 compliant (but not all optional 1.1 features are supported).
350 > Support for Perl Compatible Regular Expressions in the configuration files, and
351 generally a more sophisticated and flexible configuration syntax over
357 > Improved cookie management features (e.g. session based cookies).
367 > Bypass many click-tracking scripts (avoids script redirection).
372 > Multi-threaded (POSIX and native threads).
377 > User-customizable HTML templates for all proxy-generated pages (e.g. "blocked" page).
382 > Auto-detection and re-reading of config file changes.
387 > Improved signal handling, and a true daemon mode (Unix).
392 > Every feature now controllable on a per-site or per-location basis, configuration
393 more powerful and versatile over-all.
398 > Many smaller new features added, limitations and bugs removed, and security holes fixed.
411 >1.4. What is a <SPAN
420 > A web proxy is a service, based on a software such as <SPAN
424 that clients (i.e. browsers) can use instead of connecting directly to the web
425 servers on the Internet. The clients then ask the proxy to fetch the objects
426 they need (web pages, images, movies etc) on their behalf, and when the proxy
427 has done so, it hands the results back to the client.
430 > There are many reasons to use web proxies, such as security (firewalling),
431 efficiency (caching) and others, and there are just as many different proxies
432 to accommodate those needs.
438 > is a proxy that is solely focused on privacy
439 protection and junk elimination. Sitting between your browser(s) and the Internet,
440 it is in a perfect position to filter outbound personal information that your
441 browser is leaking, as well as inbound junk. It uses a variety of techniques to do
442 this, all of which are under your control via the various configuration
457 an ad, and what is not?</H3
462 >'s approach to blocking ads is twofold:</P
464 > First, there are certain patterns in the <SPAN
471 of banner images. This applies to both the path (you wouldn't guess how many
472 web sites serve their banners from a directory called <SPAN
476 and the host (blocking the big banner hosting services like doublecklick.net
477 already helps a lot). <SPAN
480 > takes advantage of this
482 HREF="../user-manual/actions-file.html#AF-PATTERNS"
486 > to sort out and block the requests for banners.</P
488 > Second, banners tend to come in certain <SPAN
495 can't tell the size of an image by its URL without downloading it, and if you
496 do, it's too late to save bandwidth. Therefore, <SPAN
500 also inspects the HTML sources of web pages while they are loaded, and replaces
501 references to images with standard banner sizes by dummy references, so that
502 your browser doesn't request them anymore in the first place.</P
504 > Both of this involves a certain amount of guesswork and is, of course, freely
518 This does not sound very scientific.</H3
520 > Actually, it's a black art ;-) And yes, it is always possible to have a broad
521 rule accidentally block or change something by mistake. There is a good chance
522 you may run into such a situation at some point. It is tricky writing rules to
523 cover every conceivable possibility, and not occasionally get false positives.</P
525 > But this should not be a big concern since the
529 > configuration is very flexible, and
530 includes tools to help identify these types of situations so they can be
531 addressed as needed, allowing you to customize your installation.
533 HREF="trouble.html#BADSITE"
534 >See the Troubleshooting section below</A
544 >1.7. My browser does the same things as
554 > Modern browsers do indeed have <SPAN
561 functionality as <SPAN
565 adequate for you. But <SPAN
569 versatile and powerful, and can do a number of things that browsers just can't.
572 > In addition, a proxy is good choice if you use multiple browsers, or
573 have a LAN with multiple computers. This way all the configuration
574 is in one place, and you don't have to maintain a similar configuration
575 for possibly many browsers.
585 >1.8. Is there is a license or fee? What about a
586 warranty? Registration?</H3
591 > is licensed under the <A
592 HREF="http://www.gnu.org/copyleft/gpl.html"
594 >GNU General Public License (GPL)</A
596 It is free to use, copy, modify or distribute as you wish under the terms of this
597 license. Please see the <A
598 HREF="copyright.html"
601 information on the license and copyright. Or the <TT
605 that should be included.
614 > of any kind, expressed, implied or otherwise.
615 That is something that would cost real money ;-) There is no registration either.
636 >1.9. I would like to help you, what do I do?</H3
642 NAME="JOINTEAM-MONEY"
644 >1.9.1. Money Money Money</H4
646 > We, of course, welcome donations and could use money for domain registering,
647 buying software to test <SPAN
650 > with, and, of course,
651 for regular world-wide get-togethers (hahaha). If you enjoy the software and feel
652 like helping us with a donation, just <A
653 HREF="mailto:developers@privoxy.org"
663 NAME="JOINTEAM-SOFTWARE"
667 > If you are a vendor of a web-related software like a browser, web server
668 or proxy, and would like us to ensure that <SPAN
672 runs smoothly with your product, you might consider supplying us with a
673 copy or license. We can't, however, guarantee that we will fix all potential
674 compatibility issues as a result.</P
683 >1.9.3. You want to work with us?</H4
685 > Well, helping the team is always a good idea. We welcome new developers,
686 packaging gurus or documentation writers. Simply <A
687 HREF="https://sourceforge.net/account/register.php"
689 >get an account on SourceForge.net</A
691 and mail your id to the <A
692 HREF="mailto:developers@privoxy.org"
697 HREF="../developer-manual/index.html"
699 >Developer's Manual</A
702 > Once we have added you to the team, you'll have write access to the <A
703 HREF="http://sourceforge.net/cvs/?group_id=11118"
707 together we'll find a suitable task for you.</P
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