{"id":34,"date":"2010-01-15T08:12:11","date_gmt":"2010-01-15T08:12:11","guid":{"rendered":"http:\/\/www.proxville.com\/guides\/?p=34"},"modified":"2024-09-02T12:10:26","modified_gmt":"2024-09-02T12:10:26","slug":"content-filter","status":"publish","type":"post","link":"https:\/\/www.proxville.com\/guides\/content-filter","title":{"rendered":"What is a Content filter"},"content":{"rendered":"<p style=\"float: left;margin: 4px;\"><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-2174962885476117\"\r\n     crossorigin=\"anonymous\"><\/script>\r\n<!-- Responsive -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-client=\"ca-pub-2174962885476117\"\r\n     data-ad-slot=\"5070544181\"\r\n     data-ad-format=\"auto\"\r\n     data-full-width-responsive=\"true\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/p><p>Many schools,workplaces, and colleges\u00a0 restrict websites and online  services that they provide. This is done with a  specialized proxy, called a content filter (both commercial and free  products available), or by a cache-extension protocol such as ICAP,  which allows the plug-in extensions to a storage architecture cached  open.<\/p>\n<p>Applications submitted to the open internet must first  pass through a proxy filter output. Web filtering company offers a  database of URL patterns (regular expressions) with associated content  attributes. This database is updated weekly by subscription throughout  the site, such as a virus filter subscription. The administrator  instructs the web filter to ban broad categories of content (such as  sports, pornography, online shopping, gambling, or social networking).  Requests that match a banned URL pattern are rejected immediately.<\/p>\n<p>Assuming the requested URL is acceptable, the content is brought by the  proxy. At this point a dynamic filter may be applied on the return  path. For example, JPEG files may be blocked based on Fleshtones parties  or dynamically filters the language could detect the language. If the  content is rejected an HTTP error is returned to seek and nothing is  cached.<\/p>\n<p>Most web filtering companies use a robot to crawl the  Internet to scale that assesses the probability that a content is a  certain type (ie &#8220;This content is 70% chance of porn, 40% chance sports,  and 30% chance of news &#8220;could be the result for a website). The  resulting database are corrected by manual labor based on complaints or  known flaws in the content matching algorithms.<\/p>\n<p>Filtering Web  proxies are not capable of looking inside Secure Sockets HTTP  transactions, assuming the trust chain of SSL \/ TLS has been handled. As  a result, users who wish to avoid web filtering normally search the  internet for an open and anonymous HTTPS transparent proxy. Next, set  your browser to proxy all requests through the Web filter to this  anonymous proxy. These applications will be encrypted with https. Web  Filter can not distinguish these transactions from, say, a legitimate  access to a personal finance website. Thus, content filters are only  effective against unsophisticated users.<\/p>\n<p>As mentioned above, \/  TLS SSL chain-of-trust is based on trusted root certificate authorities,  working in an environment where the customer is managed by the  organization, trust can be given to a root certificate which public key  is known by the proxy. In particular, a root certificate generated by  the proxy is installed in the form of lists of CA by the IT staff. In  such scenarios, the analysis of proxy for the contents of an SSL \/ TLS  transaction is possible. The proxy is effective functioning of an attack  &#8220;man-in-the-middle, allowed by customer trust a root certificate has  representation.<\/p>\n<p>A special case of web proxies are &#8220;CGI  proxies.&#8221; These are websites that allow a user to access a site through  them. Usually use PHP or CGI to implement the proxy functionality. These  types of proxy servers are often used to access web sites blocked by  corporate or school proxies. Since it also hides the user&#8217;s own IP  address for web sites that access via the proxy, it is sometimes used to  gain a degree of anonymity, called &#8220;Proxy Prevention.&#8221;<\/p>\n<p><\/p>","protected":false},"excerpt":{"rendered":"<p>Many schools,workplaces, and colleges\u00a0 restrict websites and online services that they provide. This is done with a specialized proxy, called a content filter (both commercial and free products available), or by a cache-extension protocol such as ICAP, which allows the plug-in extensions to a storage architecture cached open. Applications submitted to the open internet must [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/posts\/34"}],"collection":[{"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/comments?post=34"}],"version-history":[{"count":4,"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/posts\/34\/revisions"}],"predecessor-version":[{"id":368,"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/posts\/34\/revisions\/368"}],"wp:attachment":[{"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/media?parent=34"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/categories?post=34"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.proxville.com\/guides\/wp-json\/wp\/v2\/tags?post=34"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}