Ad filtering
Encyclopedia
Ad filtering or ad blocking is removing or altering advertising content in a webpage. Advertising can exist in a variety of forms including pictures
, animations, text, or pop-up windows
. More advanced filters allow fine-grained control of advertisements
through features such as blacklist
s, whitelists, and regular expression
filters. Certain security features also have the effect of disabling some ads.
The immediate benefits include quicker loading and cleaner looking Web pages free from advertisements, lower resource waste (bandwidth, CPU, memory, etc.), and privacy benefits gained through the exclusion of the tracking and profiling systems of ad delivery platforms. The cost is decreased revenue to the website that was sustained by advertisements.http://arstechnica.com/business/news/2010/03/why-ad-blocking-is-devastating-to-the-sites-you-love.ars
Almost all modern web browsers include a pop-up blocker. Opera
, Konqueror
, Maxthon
2, and Internet Explorer 8
also include content filtering, which prevents external files such as images or JavaScript files from loading. Content filtering can be added to Mozilla Firefox
and related browsers with Adblock Plus, and a number of sources provide regularly updated filter lists. For Internet Explorer
there are several add-ons available like Simple Adblock, IE7Pro
, Adblock Pro and Quero that also allows users to temporarily unblock blocked content. A rudimentary content blocking feature is integrated in Opera
and does not require an add-on. For Google Chrome
, which has had extensions available since v2.0, the AdSweep and FlashBlock extensions are available, as well as AdBlock Plus and AdBlockforChrome. Another method for filtering advertisements uses CSS
rules to hide specific HTML
and XHTML
elements
.
, Squid, Proximodo, Adextinguisher, Ad Muncher, Death 2 Ads, Guidescope and Proxomitron
. The main advantage of the method is freedom from implementation limitations (browser, working techniques) and centralization of control (the proxy can be used by many users). The major drawback is that the proxy sees only raw content and thus it's difficult to handle JavaScript
-generated content.
This method exploits the fact that most operating systems store a file with IP address, domain name pairs which is consulted by most browsers before using a DNS server to look up a domain name. By assigning the local 127.0.0.1 IP number to each known Ad server, the user directs traffic intended to reach each Ad server to the local machine. Running a suitable web server locally the ad content can be replaced with anything the user wishes.
.
Image
An image is an artifact, for example a two-dimensional picture, that has a similar appearance to some subject—usually a physical object or a person.-Characteristics:...
, animations, text, or pop-up windows
Pop-up ad
Pop-up ads or pop-ups are a form of online advertising on the World Wide Web intended to attract web traffic or capture email addresses. Pop-ups are generally new web browser windows to display advertisements...
. More advanced filters allow fine-grained control of advertisements
Online advertising
Online advertising is a form of promotion that uses the Internet and World Wide Web to deliver marketing messages to attract customers. Examples of online advertising include contextual ads on search engine results pages, banner ads, blogs, Rich Media Ads, Social network advertising, interstitial...
through features such as blacklist
Blacklist
A blacklist is a list or register of entities who, for one reason or another, are being denied a particular privilege, service, mobility, access or recognition. As a verb, to blacklist can mean to deny someone work in a particular field, or to ostracize a person from a certain social circle...
s, whitelists, and regular expression
Regular expression
In computing, a regular expression provides a concise and flexible means for "matching" strings of text, such as particular characters, words, or patterns of characters. Abbreviations for "regular expression" include "regex" and "regexp"...
filters. Certain security features also have the effect of disabling some ads.
The immediate benefits include quicker loading and cleaner looking Web pages free from advertisements, lower resource waste (bandwidth, CPU, memory, etc.), and privacy benefits gained through the exclusion of the tracking and profiling systems of ad delivery platforms. The cost is decreased revenue to the website that was sustained by advertisements.http://arstechnica.com/business/news/2010/03/why-ad-blocking-is-devastating-to-the-sites-you-love.ars
Browser Integration
Opera (web browser)
Opera is a web browser and Internet suite developed by Opera Software with over 200 million users worldwide. The browser handles common Internet-related tasks such as displaying web sites, sending and receiving e-mail messages, managing contacts, chatting on IRC, downloading files via BitTorrent,...
, Konqueror
Konqueror
Not to be confused with the Conqueror web browser.Konqueror is a web browser and file manager that provides file-viewer functionality for file systems such as local files, files on a remote ftp server and files in a disk image. It is a core part of the KDE desktop environment...
, Maxthon
Maxthon
Maxthon is a free web browser for Microsoft Windows. The latest release, Maxthon 3, supports both the Trident and the WebKit rendering engines....
2, and Internet Explorer 8
Internet Explorer 8
Windows Internet Explorer 8 is a web browser developed by Microsoft in the Internet Explorer browser series. The browser was released on March 19, 2009 for Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, and Windows 7. Both 32-bit and 64-bit builds are available...
also include content filtering, which prevents external files such as images or JavaScript files from loading. Content filtering can be added to Mozilla Firefox
Mozilla Firefox
Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers...
and related browsers with Adblock Plus, and a number of sources provide regularly updated filter lists. For Internet Explorer
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
there are several add-ons available like Simple Adblock, IE7Pro
IE7Pro
IE7Pro is an add-on for Internet Explorer 6, 7, 8, and 9 that aims to enhance the feature set provided by the browser. IE7Pro adds features such as tab enhancement, an ad blocker and flash blocker, mouse gestures, inline search, privacy enhancements, online bookmark service, Greasemonkey-like user...
, Adblock Pro and Quero that also allows users to temporarily unblock blocked content. A rudimentary content blocking feature is integrated in Opera
Opera (web browser)
Opera is a web browser and Internet suite developed by Opera Software with over 200 million users worldwide. The browser handles common Internet-related tasks such as displaying web sites, sending and receiving e-mail messages, managing contacts, chatting on IRC, downloading files via BitTorrent,...
and does not require an add-on. For Google Chrome
Google Chrome
Google Chrome is a web browser developed by Google that uses the WebKit layout engine. It was first released as a beta version for Microsoft Windows on September 2, 2008, and the public stable release was on December 11, 2008. The name is derived from the graphical user interface frame, or...
, which has had extensions available since v2.0, the AdSweep and FlashBlock extensions are available, as well as AdBlock Plus and AdBlockforChrome. Another method for filtering advertisements uses CSS
Cascading Style Sheets
Cascading Style Sheets is a style sheet language used to describe the presentation semantics of a document written in a markup language...
rules to hide specific HTML
HTML
HyperText Markup Language is the predominant markup language for web pages. HTML elements are the basic building-blocks of webpages....
and XHTML
XHTML
XHTML is a family of XML markup languages that mirror or extend versions of the widely-used Hypertext Markup Language , the language in which web pages are written....
elements
HTML element
An HTML element is an individual component of an HTML document. HTML documents are composed of a tree of HTML elements and other nodes, such as text nodes. Each element can have attributes specified. Elements can also have content, including other elements and text. HTML elements represent...
.
External programs
A number of external applications offer ad filtering as a primary or additional feature. A traditional solution is to customize an HTTP proxy (or web proxy) to filter content. These programs work by caching and filtering content before it is displayed in a user's browser. This provides an opportunity to remove not only ads but also content which may be offensive, inappropriate, or simply junk. Popular proxy software which blocks content effectively include PrivoxyPrivoxy
Privoxy is a non-caching web proxy with filtering capabilities for enhancing privacy, modifying web page data and HTTP headers before the page is rendered by the browser. Privoxy is a "privacy enhancing proxy", filtering Web pages and removing advertisements...
, Squid, Proximodo, Adextinguisher, Ad Muncher, Death 2 Ads, Guidescope and Proxomitron
Proxomitron
Proxomitron, the Universal Web Filter, is a filtering web proxy written by Scott R. Lemmon. This program was originally designed to run under Windows 95....
. The main advantage of the method is freedom from implementation limitations (browser, working techniques) and centralization of control (the proxy can be used by many users). The major drawback is that the proxy sees only raw content and thus it's difficult to handle JavaScript
JavaScript
JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....
-generated content.
Hosts file
Further information: hosts file.This method exploits the fact that most operating systems store a file with IP address, domain name pairs which is consulted by most browsers before using a DNS server to look up a domain name. By assigning the local 127.0.0.1 IP number to each known Ad server, the user directs traffic intended to reach each Ad server to the local machine. Running a suitable web server locally the ad content can be replaced with anything the user wishes.
DNS Filtering
Advertising can be blocked by using a DNS server which is configured to block access to domains or hostnames which are known to serve ads. Examples are AdBarricade, DNS Redirector, DNSKong and OpenDNSOpenDNS
OpenDNS is a DNS resolution service. OpenDNS extends DNS adding features such as misspelling correction, phishing protection, and optional content filtering...
.
See also
- Ad server
- Adversarial information retrievalAdversarial information retrievalAdversarial information retrieval is a topic in information retrieval related to strategies for working with a data source where some portion of it has been manipulated maliciously. Tasks can include gathering, indexing, filtering, retrieving and ranking information from such a data source...
- Hosts file filtering
- Proxy server#Content filter
- ProxomitronProxomitronProxomitron, the Universal Web Filter, is a filtering web proxy written by Scott R. Lemmon. This program was originally designed to run under Windows 95....
- Adblock Plus
- AdBlock (Chrome)AdBlock (Chrome)AdBlock is a content-filtering extension for the Google Chrome and Apple Safari web browsers. AdBlock allows users to prevent page elements, such as advertisements, from being displayed. AdBlock is the most popular extension for Google Chrome...
Common advertising techniques
- Pop-up adPop-up adPop-up ads or pop-ups are a form of online advertising on the World Wide Web intended to attract web traffic or capture email addresses. Pop-ups are generally new web browser windows to display advertisements...
s - Plain textPlain textIn computing, plain text is the contents of an ordinary sequential file readable as textual material without much processing, usually opposed to formatted text....
- Ad bannersWeb bannerA web banner or banner ad is a form of advertising on the World Wide Web delivered by an ad server. This form of online advertising entails embedding an advertisement into a web page. It is intended to attract traffic to a website by linking to the website of the advertiser...
- Flash animations
- Keyword hyperlinksKeyword advertisingKeyword advertising refers to any advertising that is linked to specific words or phrases. Common forms of keyword advertising are known by many other terms including pay per click and cost per action...
(for example Vibrant Media's IntelliTXTIntelliTXTIntelliTXT is an "in-text" advertisement platform developed by Vibrant Media, and is an example of keyword advertising. Website authors insert a script into their pages which calls the IntelliTXT platform when a viewer views the page; this script then finds keywords on the page and double...
) - Browser plugins/extensions (often labeled as adwareAdwareAdware, or advertising-supported software, is any software package which automatically plays, displays, or downloads advertisements to a computer. These advertisements can be in the form of a pop-up. They may also be in the user interface of the software or on a screen presented to the user during...
) - External applications (see adwareAdwareAdware, or advertising-supported software, is any software package which automatically plays, displays, or downloads advertisements to a computer. These advertisements can be in the form of a pop-up. They may also be in the user interface of the software or on a screen presented to the user during...
, spywareSpywareSpyware is a type of malware that can be installed on computers, and which collects small pieces of information about users without their knowledge. The presence of spyware is typically hidden from the user, and can be difficult to detect. Typically, spyware is secretly installed on the user's...
)