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38 >Privoxy Frequently Asked Questions</TH
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73 >1. General Information</A
81 >1.1. What is this new version of <SPAN
87 > In the beginning, there was the
89 HREF="http://www.junkbusters.com/ijb.html"
93 >Internet Junkbuster</SPAN
96 by Anonymous Coders and <A
97 HREF="http://www.junkbusters.com/"
101 >. It saved many users a lot of pain in the early days of
102 web advertising and user tracking.</P
104 > But the web, its protocols and standards, and with it, the techniques for
105 forcing users to consume ads, give up autonomy over their browsing, and
106 for spying on them, kept evolving. Unfortunately, the <SPAN
110 > did not. Version 2.0.2, published in 1998, was
111 (and is) the last official
113 HREF="http://www.junkbusters.com/ijbdist.html#release"
118 HREF="http://www.junkbusters.com"
120 >Junkbusters Corporation</A
122 Fortunately, it had been released under the GNU
124 HREF="http://www.gnu.org/licenses/gpl.html"
127 >, which allowed further
128 development by others.</P
130 > So Stefan Waldherr started maintaining an
132 HREF="http://www.waldherr.org/junkbuster/"
134 >improved version of the
136 >, to which eventually a number of people contributed patches.
137 It could already replace banners with a transparent image, and had a first
138 version of pop-up killing, but it was still very closely based on the
139 original, with all its limitations, such as the lack of HTTP/1.1 support,
140 flexible per-site configuration, or content modification. The last release
141 from this effort was version 2.0.2-10, published in 2000.</P
145 HREF="http://www.privoxy.org/user-manual/copyright.html#AUTHORS"
149 picked up the thread, and started turning the software inside out, upside down,
150 and then reassembled it, adding many
152 HREF="http://www.privoxy.org/user-manual/introduction.html#FEATURES"
158 > The result of this is <SPAN
162 stable release, 3.0, is due late summer or early fall 2002.
174 >? Why a name change at all?</A
185 >Privacy Enhancing Proxy</I
188 modification and junk suppression allow you to browse your
198 HREF="http://junkbusters.com/"
200 >Junkbusters Corporation</A
202 continues to offer their original version of the <SPAN
210 >-derived software under the same name
213 > There are also potential legal complications from the continued use of the
217 > name, which is a registered trademark of
219 HREF="http://junkbusters.com/"
221 >Junkbusters Corporation</A
223 There are, however, no objections from Junkbusters Corporation to the
227 > project itself, and they, in fact, still
228 share our ideals and goals.</P
230 > The developers also believed that there are so many changes from the original
231 code, that it was time to make a clean break from the past and make
232 a name in their own right, especially now with the pending
233 release of version 3.0.</P
258 > left off. All the old features remain.
262 > still blocks ads and banners,
263 still manages cookies, and still helps protect your privacy. But, these are
264 all enhanced, and many new features have been added, all in the same vein.
267 > The configuration has changed significantly as well. This is something that
268 users will notice right off the bat if upgrading from
282 > and much more has been
283 combined into the <SPAN
286 > files, with a completely different
288 HREF="../user-manual/upgradersnote.html"
297 >'s new features include:</P
304 > Integrated browser based configuration and control utility at <A
305 HREF="http://config.privoxy.org/"
307 >http://config.privoxy.org/</A
314 tracing of rule and filter effects. Remote toggling.
319 > Web page content filtering (removes banners based on size,
323 >, JavaScript and HTML annoyances, pop-up windows, etc.)
328 > Modularized configuration that allows for standard settings and
329 user settings to reside in separate files, so that installing updated
330 actions files won't overwrite individual user settings.
335 > HTTP/1.1 compliant (but not all optional 1.1 features are supported).
340 > Support for Perl Compatible Regular Expressions in the configuration files, and
341 generally a more sophisticated and flexible configuration syntax over
347 > Improved cookie management features (e.g. session based cookies).
357 > Bypass many click-tracking scripts (avoids script redirection).
362 > Multi-threaded (POSIX and native threads).
367 > User-customizable HTML templates for all proxy-generated pages (e.g. "blocked" page).
372 > Auto-detection and re-reading of config file changes.
377 > Improved signal handling, and a true daemon mode (Unix).
382 > Every feature now controllable on a per-site or per-location basis, configuration
383 more powerful and versatile over-all.
388 > Many smaller new features added, limitations and bugs removed, and security holes fixed.
400 >1.4. What is a <SPAN
410 > A web proxy is a service, based on a software such as <SPAN
414 that clients (i.e. browsers) can use instead of connecting directly to the web
415 servers on the Internet. The clients then ask the proxy to fetch the objects
416 they need (web pages, images, movies etc) on their behalf, and when the proxy
417 has done so, it hands the results back to the client.
420 > There are many reasons to use web proxies, such as security (firewalling),
421 efficiency (caching) and others, and there are just as many different proxies
422 to accommodate those needs.
428 > is a proxy that is solely focused on privacy
429 protection and junk elimination. Sitting between your browser(s) and the Internet,
430 it is in a perfect position to filter outbound personal information that your
431 browser is leaking, as well as inbound junk. It uses a variety of techniques to do
432 this, all of which are under your control via the various configuration
446 an ad, and what is not?</A
452 >'s approach to blocking ads is twofold:</P
454 > First, there are certain patterns in the <I
458 of banner images. This applies to both the path (you wouldn't guess how many
459 web sites serve their banners from a directory called <SPAN
463 and the host (blocking the big banner hosting services like doublecklick.net
464 already helps a lot). <SPAN
467 > takes advantage of this
469 HREF="../user-manual/actions-file.html#AF-PATTERNS"
473 > to sort out and block the requests for banners.</P
475 > Second, banners tend to come in certain <I
479 can't tell the size of an image by its URL without downloading it, and if you
480 do, it's too late to save bandwidth. Therefore, <SPAN
484 also inspects the HTML sources of web pages while they are loaded, and replaces
485 references to images with standard banner sizes by dummy references, so that
486 your browser doesn't request them anymore in the first place.</P
488 > Both of this involves a certain amount of guesswork and is, of course, freely
501 This does not sound very scientific.</A
504 > Actually, it's a black art ;-) And yes, it is always possible to have a broad
505 rule accidentally block or change something by mistake. There is a good chance
506 you may run into such a situation at some point. It is tricky writing rules to
507 cover every conceivable possibility, and not occasionally get false positives.</P
509 > But this should not be a big concern since the
513 > configuration is very flexible, and
514 includes tools to help identify these types of situations so they can be
515 addressed as needed, allowing you to customize your installation.
517 HREF="trouble.html#BADSITE"
518 >See the Troubleshooting section below</A
527 >1.7. My browser does the same things as
538 > Modern browsers do indeed have <I
542 functionality as <SPAN
546 adequate for you. But <SPAN
550 versatile and powerful, and can do a number of things that browsers just can't.
553 > In addition, a proxy is good choice if you use multiple browsers, or
554 have a LAN with multiple computers. This way all the configuration
555 is in one place, and you don't have to maintain a similar configuration
556 for possibly many browsers.
565 >1.8. Is there is a license or fee? What about a
566 warranty? Registration?</A
572 > is licensed under the <A
573 HREF="http://www.gnu.org/copyleft/gpl.html"
575 >GNU General Public License (GPL)</A
577 It is free to use, copy, modify or distribute as you wish under the terms of this
578 license. Please see the <A
579 HREF="copyright.html"
582 information on the license and copyright. Or the <TT
586 that should be included.
592 > of any kind, expressed, implied or otherwise.
593 That is something that would cost real money ;-) There is no registration either.
610 >1.9. I would like to help you, what do I do?</A
617 NAME="JOINTEAM-MONEY"
618 >1.9.1. Money Money Money</A
621 > We, of course, welcome donations and could use money for domain registering,
622 buying software to test <SPAN
625 > with, and, of course,
626 for regular world-wide get-togethers (hahaha). If you enjoy the software and feel
627 like helping us with a donation, just <A
628 HREF="mailto:developers@privoxy.org"
638 NAME="JOINTEAM-SOFTWARE"
642 > If you are a vendor of a web-related software like a browser, web server
643 or proxy, and would like us to ensure that <SPAN
647 runs smoothly with your product, you might consider supplying us with a
648 copy or license. We can't, however, guarantee that we will fix all potential
649 compatibility issues as a result.</P
657 >1.9.3. You want to work with us?</A
660 > Well, helping the team is always a good idea. We welcome new developers,
661 packaging gurus or documentation writers. Simply <A
662 HREF="https://sourceforge.net/account/register.php"
664 >get an account on SourceForge.net</A
666 and mail your id to the <A
667 HREF="mailto:developers@privoxy.org"
672 HREF="../developer-manual/index.html"
674 >Developer's Manual</A
677 > Once we have added you to the team, you'll have write access to the <A
678 HREF="http://sourceforge.net/cvs/?group_id=11118"
682 together we'll find a suitable task for you.</P
717 HREF="installation.html"
726 >Privoxy Frequently Asked Questions</TD